Microscope Objectives | Surplus Network

Zeiss Plan 100x /1.25 Oel 160/- 46 19 10-9902 Microscope Objective

USA

Zeiss Plan 100x /1.25 Oel 160/- 46...

$59.95 USD

Zeiss Plan 100x /1.25 Oel 160/- 46...

$59.95 USD

GENERIC FL 40/1.0 GLYC 160/0.17 GLYCERIN MICROSCOPE OBJECTIVE - 40X RMS

USA

GENERIC FL 40/1.0 GLYC 160/0.17...

$59.95 USD

GENERIC FL 40/1.0 GLYC 160/0.17...

$59.95 USD

Leitz Wetzlar Germany Fluoresz 25x / 0.75 160/0.17 Microscope Objective 25

USA

Leitz Wetzlar Germany Fluoresz 25x...

$119.99 USD

Leitz Wetzlar Germany Fluoresz 25x...

$119.99 USD

Leitz Wetzlar Germany FLUORESZENZ 10x / 0.45 OEL 170/- Microscope Objective 10

USA

Leitz Wetzlar Germany FLUORESZENZ 10x...

$169.95 USD

Leitz Wetzlar Germany FLUORESZENZ 10x...

$169.95 USD

AmScope A4X-YX-V460 4X Achromatic Microscope Objective + Container

USA

AmScope A4X-YX-V460 4X Achromatic...

$12.99 USD

AmScope A4X-YX-V460 4X Achromatic...

$12.99 USD

Swift LWD 40x OBJECTIIVE 0.65 NA, for SWIFT FM-31 Field Master Microscope Lens

USA

Swift LWD 40x OBJECTIIVE 0.65 NA, for...

$25.99 USD

Swift LWD 40x OBJECTIIVE 0.65 NA, for...

$25.99 USD

Olympus EH Microscope Stage w/specimen holder

USA

Olympus EH Microscope Stage...

$24.99 USD

Olympus EH Microscope Stage...

$24.99 USD

Nikon CFI Plan APO VC Series 20X DIC Microscope Objective Apochromat OEM

USA

Nikon CFI Plan APO VC Series 20X DIC...

$157.50 USD

Nikon CFI Plan APO VC Series 20X DIC...

$157.50 USD

AmScope A60X-YX-V460 60X Achromatic Microscope Objective + Container

USA

AmScope A60X-YX-V460 60X Achromatic...

$35.99 USD

AmScope A60X-YX-V460 60X Achromatic...

$35.99 USD

Wild 40/0.65 Ph D=0.17 objective Lens

USA

Wild 40/0.65 Ph D=0.17 objective Lens

$6.99 USD

Wild 40/0.65 Ph D=0.17 objective Lens

$6.99 USD

AmScope 20X Achromatic Microscope Objective for Compound Microscope

USA

AmScope 20X Achromatic Microscope...

$22.99 USD

AmScope 20X Achromatic Microscope...

$22.99 USD

AmScope 100X (Oil) Achromatic Microscope Objective for Compound Microscopes

USA

AmScope 100X (Oil) Achromatic...

$22.99 USD

AmScope 100X (Oil) Achromatic...

$22.99 USD

Leitz Wetzlar Germany NPL FLUOTAR 16x / 0.45 160/0.17 Microscope Objective 16

USA

Leitz Wetzlar Germany NPL FLUOTAR ...

$159.99 USD

Leitz Wetzlar Germany NPL FLUOTAR ...

$159.99 USD

AmScope 4X Plan Achromatic Compound Microscope Objective Lens

USA

AmScope 4X Plan Achromatic Compound...

$20.99 USD

AmScope 4X Plan Achromatic Compound...

$20.99 USD

AmScope 40X (Spring) Achromatic Microscope Objective for Compound Microscopes

USA

AmScope 40X (Spring) Achromatic...

$20.99 USD

AmScope 40X (Spring) Achromatic...

$20.99 USD

Zeiss NEOFLUAR 25x /0.60 160/0.17 46 06 20-9902 Microscope Objective 25

USA

Zeiss NEOFLUAR 25x /0.60 160/0.17 46...

$149.95 USD

Zeiss NEOFLUAR 25x /0.60 160/0.17 46...

$149.95 USD

Plastic Container for Microscope Objective with RMS Thread

USA

Plastic Container for Microscope...

$4.99 USD

Plastic Container for Microscope...

$4.99 USD

Leica Leitz PHOTAR 1:4/50 50mm Comparison Microscope Objective Macro Lens

USA

Leica Leitz PHOTAR 1:4/50 50mm...

$189.00 USD

Leica Leitz PHOTAR 1:4/50 50mm...

$189.00 USD

Leitz Wetzlar Germany 40x / 0.65 EF 160/0.17 Microscope Objective 40 C

USA

Leitz Wetzlar Germany 40x / 0.65 EF...

$49.99 USD

Leitz Wetzlar Germany 40x / 0.65 EF...

$49.99 USD

Leitz Wetzlar Germany 4x / 0.12 170/- Microscope Objective 4

USA

Leitz Wetzlar Germany 4x / 0.12 ...

$49.99 USD

Leitz Wetzlar Germany 4x / 0.12 ...

$49.99 USD

Olympus Microscope Objective A10 PO 10x/0.25 160/0.17 Strain Free Pol

USA

Olympus Microscope Objective A10 PO...

$99.99 USD

Olympus Microscope Objective A10 PO...

$99.99 USD

OLYMPUS A40 PL 0.65 160/0.17 MICROSCOPE OBJECTIVE LENS

USA

OLYMPUS A40 PL 0.65 160/0.17...

$99.99 USD

OLYMPUS A40 PL 0.65 160/0.17...

$99.99 USD

Canon EOS To RMS Microscope Objective Kit For Micro Photography W/ 4X Objective

China

Canon EOS To RMS Microscope Objective...

$23.20 USD

Canon EOS To RMS Microscope Objective...

$23.20 USD

Olympus Microscope Objective Lens 4X (0.10) 436413.

USA

Olympus Microscope Objective Lens 4X...

$15.00 USD

Olympus Microscope Objective Lens 4X...

$15.00 USD

Lot Of 5 Microscope Objective 100x Oil 160/0.17

USA

Lot Of 5 Microscope Objective 100x...

$72.00 USD

Lot Of 5 Microscope Objective 100x...

$72.00 USD

Nikon 10x 0.25 Microscope Objective Fast Free Shipping Included

USA

Nikon 10x 0.25 Microscope Objective...

$11.04 USD

Nikon 10x 0.25 Microscope Objective...

$11.04 USD

*New* Nikon Plan 40x/0.65 WD Objective

USA

*New* Nikon Plan 40x/0.65 WD Objective

$375.00 USD

*New* Nikon Plan 40x/0.65 WD Objective

$375.00 USD

Microscope Objective 4x

USA

Microscope Objective 4x

$7.95 USD

Microscope Objective 4x

$7.95 USD

OLYMPUS MPlanApo 2.5X / 0.08 Microscope Objective Lens

South

OLYMPUS MPlanApo 2.5X / 0.08...

$299.90 USD

OLYMPUS MPlanApo 2.5X / 0.08...

$299.90 USD

Nikon Plan Fluor 60x/0.85 DIC M Free International Shipping

Japan

Nikon Plan Fluor 60x/0.85 DIC M Free...

$549.00 USD

Nikon Plan Fluor 60x/0.85 DIC M Free...

$549.00 USD

4X 10X 40X 100X Infinity Plan Objective Lens f/ Olympus UIS2 Microscope 45mm RMS

China

4X 10X 40X 100X Infinity Plan...

$35.90 USD

4X 10X 40X 100X Infinity Plan...

$35.90 USD

5X Infinity Nelsonian Achrovid Microscope Objective. NEW.

USA

5X Infinity Nelsonian Achrovid...

$149.00 USD

5X Infinity Nelsonian Achrovid...

$149.00 USD

Leitz PL 2.5X Plan Microscope Objective 160/- Lens Macro Photography 160mm

USA

Leitz PL 2.5X Plan Microscope...

$149.00 USD

Leitz PL 2.5X Plan Microscope...

$149.00 USD

Zeiss A-Plan 5x/0.12 Infinity Corrected Microscope Objective Part # 441020 AXIO

USA

Zeiss A-Plan 5x/0.12 Infinity...

$149.00 USD

Zeiss A-Plan 5x/0.12 Infinity...

$149.00 USD

Nikon Microscope binocular head for E100, 200, 400, 600

USA

Nikon Microscope binocular head for...

$149.00 USD

Nikon Microscope binocular head for...

$149.00 USD

AmScope 60X Plan Achromatic Objective Lens with Knurled Ring for Microscopes

USA

AmScope 60X Plan Achromatic Objective...

$68.99 USD

AmScope 60X Plan Achromatic Objective...

$68.99 USD

AmScope 60X Achromatic Microscope Objective for Compound Microscope

USA

AmScope 60X Achromatic Microscope...

$39.99 USD

AmScope 60X Achromatic Microscope...

$39.99 USD

Zeiss 46-04-01-9904, 10/0.22 Ph1 Microscope Objective

USA

Zeiss 46-04-01-9904, 10/0.22 Ph1...

$39.99 USD

Zeiss 46-04-01-9904, 10/0.22 Ph1...

$39.99 USD

Carl Zeiss f = 250mm T* OPMI Surgical Microscope Objective Lens

USA

Carl Zeiss f = 250mm T* OPMI ...

$269.95 USD

Carl Zeiss f = 250mm T* OPMI ...

$269.95 USD

4X E Plan Nikon Microscope Objective

USA

4X E Plan Nikon Microscope Objective

$119.00 USD

4X E Plan Nikon Microscope Objective

$119.00 USD

Leitz Wetzlar Objective Lens HL 20X / 0.30 DF Microscope

USA

Leitz Wetzlar Objective Lens HL 20X /...

$38.00 USD

Leitz Wetzlar Objective Lens HL 20X /...

$38.00 USD

Olympus MPlanFL N 20x Objective 0.45NA Infinity MPLFLN20X Semi Apochromat APO

USA

Olympus MPlanFL N 20x Objective...

$227.50 USD

Olympus MPlanFL N 20x Objective...

$227.50 USD

Olympus Microscope Objectives 4x, 10x , 40x ,100x Japan , REFURBISHED Set of 4

USA

Olympus Microscope Objectives 4x, 10x...

$124.97 USD

Olympus Microscope Objectives 4x, 10x...

$124.97 USD

NIKON E PLAN 100X /1.25 160 /0.17 COVER SLIP OIL IMMERSION MICROSCOPE OBJECTIVE

USA

NIKON E PLAN 100X /1.25 160 /0.17...

$44.95 USD

NIKON E PLAN 100X /1.25 160 /0.17...

$44.95 USD

Nikon CFO Plan APO VC 20x / 0.75 Air UV Microscope Turret Objective 0500-0087

USA

Nikon CFO Plan APO VC 20x / 0.75 Air...

$159.95 USD

Nikon CFO Plan APO VC 20x / 0.75 Air...

$159.95 USD

Nikon OEM Microscope Objective 1501-9398 | Plan APO VC 20X AIR 0.75 NA UV

USA

Nikon OEM Microscope Objective...

$159.95 USD

Nikon OEM Microscope Objective...

$159.95 USD

AmScope 10X Plan Achromatic Objective Lens with Knurled Ring for Microscopes

USA

AmScope 10X Plan Achromatic Objective...

$34.99 USD

AmScope 10X Plan Achromatic Objective...

$34.99 USD

Nikon Plan 100X Oil Microscope Objective Lens 160mm

USA

Nikon Plan 100X Oil Microscope...

$34.99 USD

Nikon Plan 100X Oil Microscope...

$34.99 USD

Reichert Plan Achro 100/1.25 Oil Microscope Objective

USA

Reichert Plan Achro 100/1.25 Oil...

$18.99 USD

Reichert Plan Achro 100/1.25 Oil...

$18.99 USD

Olympus SPlan 40x /.70 160/0.17 Microscope Objective 40

USA

Olympus SPlan 40x /.70 160/0.17 ...

$189.99 USD

Olympus SPlan 40x /.70 160/0.17 ...

$189.99 USD

Nikon Plan 2x /0.05 160/- Microscope Objective

USA

Nikon Plan 2x /0.05 160/- Microscope...

$179.95 USD

Nikon Plan 2x /0.05 160/- Microscope...

$179.95 USD

WILD F=300MM STEREO & SURGICAL MICROSCOPE OBJECTIVE - M65 THREAD - 382168

USA

WILD F=300MM STEREO & SURGICAL...

$179.95 USD

WILD F=300MM STEREO & SURGICAL...

$179.95 USD

Leitz 10x microscope objective

USA

Leitz 10x microscope objective

$16.00 USD

Leitz 10x microscope objective

$16.00 USD

Bausch & Lomb (B&L) 20x / 0.40 NA 215mm TL Microscope Objective No Cover Glass

USA

Bausch & Lomb (B&L) 20x / 0.40 NA...

$27.00 USD

Bausch & Lomb (B&L) 20x / 0.40 NA...

$27.00 USD

Seven Plan 40 0.65 160/0.17 Microscope Objective Very Good Condition

USA

Seven Plan 40 0.65 160/0.17...

$98.99 USD

Seven Plan 40 0.65 160/0.17...

$98.99 USD

Zeiss 100X CP ACHROMAT Infinity /0.17 Oil Microscope Objective Lens 44 09 80

USA

Zeiss 100X CP ACHROMAT Infinity /0.17...

$89.99 USD

Zeiss 100X CP ACHROMAT Infinity /0.17...

$89.99 USD

Zeiss CP ACHROMAT 40X/0.65 ∞/0.17 Microscope Objective Lens P/N 440950 Nice!

USA

Zeiss CP ACHROMAT 40X/0.65 ∞/0.17 ...

$59.99 USD

Zeiss CP ACHROMAT 40X/0.65 ∞/0.17 ...

$59.99 USD

Zeiss 40X/0.75 ~ W ~ Water immersion Microscope Objective 160mm Ph2 Phase Contra

USA

Zeiss 40X/0.75 ~ W ~ Water immersion...

$179.00 USD

Zeiss 40X/0.75 ~ W ~ Water immersion...

$179.00 USD

Lot 3 Leitz Wetzlar Microscope Objectives um 32x / 0.30 10x / 0.25 170/- Pv 10x

USA

Lot 3 Leitz Wetzlar Microscope...

$179.00 USD

Lot 3 Leitz Wetzlar Microscope...

$179.00 USD

Nikon CF Plan 100X/0.90 WD 0.39 BD Microscope Objective

USA

Nikon CF Plan 100X/0.90 WD 0.39 BD...

$219.99 USD

Nikon CF Plan 100X/0.90 WD 0.39 BD...

$219.99 USD

Lot of 6x - LWS Microscope Objectives; SP10/0.25, PL100/1.25, SP100/1.25

USA

Lot of 6x - LWS Microscope...

$67.50 USD

Lot of 6x - LWS Microscope...

$67.50 USD

Nikon 20X DL ~ Ph2 Phase Contrast Microscope Objective w Correction Collar 160mm

USA

Nikon 20X DL ~ Ph2 Phase Contrast...

$159.00 USD

Nikon 20X DL ~ Ph2 Phase Contrast...

$159.00 USD

AmScope 40X Plan Achromatic Objective Lens with Knurled Ring for Microscope

USA

AmScope 40X Plan Achromatic Objective...

$50.99 USD

AmScope 40X Plan Achromatic Objective...

$50.99 USD

AmScope 20X Plan Achromatic Objective Lens with Knurled Ring for Microscopes

USA

AmScope 20X Plan Achromatic Objective...

$50.99 USD

AmScope 20X Plan Achromatic Objective...

$50.99 USD

NIKON ~ W 10X/0.22 Water Dipping Microscope Objective Lens

USA

NIKON ~ W 10X/0.22 Water Dipping...

$234.99 USD

NIKON ~ W 10X/0.22 Water Dipping...

$234.99 USD

Olympus LWD C A20x/0.40 Objective

USA

Olympus LWD C A20x/0.40 Objective

$119.95 USD

Olympus LWD C A20x/0.40 Objective

$119.95 USD

Olympus SPlan 40x Microscope Objective (BH CH BH2 CH2 BHTU BHS) 160mm ~ S Plan

USA

Olympus SPlan 40x Microscope...

$129.00 USD

Olympus SPlan 40x Microscope...

$129.00 USD

Zeiss Ph 2 Plan 40x /0.65 160/0.17 46 07 11-9902 Microscope Objective Ph2

USA

Zeiss Ph 2 Plan 40x /0.65 160/0.17 ...

$129.95 USD

Zeiss Ph 2 Plan 40x /0.65 160/0.17 ...

$129.95 USD

ZEISS 40X/1.0 Planapo Microscope Objective With Iris (Plan Apo) 160mm

USA

ZEISS 40X/1.0 Planapo Microscope...

$275.00 USD

ZEISS 40X/1.0 Planapo Microscope...

$275.00 USD

Nikon 20X/0.4 ~ Ph2 ~ DL Microscope Objective Phase Contrast 160mm

USA

Nikon 20X/0.4 ~ Ph2 ~ DL Microscope...

$124.99 USD

Nikon 20X/0.4 ~ Ph2 ~ DL Microscope...

$124.99 USD

OLYMPUS NEO SPLAN 20X/0.46 MICROSCOPE OBJECTIVE LENS , GOOD CONDITION

USA

OLYMPUS NEO SPLAN 20X/0.46 MICROSCOPE...

$185.00 USD

OLYMPUS NEO SPLAN 20X/0.46 MICROSCOPE...

$185.00 USD

4 Original Olympus MICROSCOPE OBJECTIVE 10x 0.25 - 4 1.10 - 40X 0.65 0.17

USA

4 Original Olympus MICROSCOPE...

$49.95 USD

4 Original Olympus MICROSCOPE...

$49.95 USD

Nikon Microscope Objective - CFN 40x/0.70 Plan 160/0.17 - Tested excellent

USA

Nikon Microscope Objective - CFN...

$165.00 USD

Nikon Microscope Objective - CFN...

$165.00 USD

MICROSCOPE OBJECTIVE LOT

USA

MICROSCOPE OBJECTIVE LOT

$50.00 USD

MICROSCOPE OBJECTIVE LOT

$50.00 USD

LEITZ 63X 1.30 160/17 OEL FLUORESCENCE FLUORESZENZ MICROSCOPE OBJECTIVE - RMS

USA

LEITZ 63X 1.30 160/17 OEL...

$164.95 USD

LEITZ 63X 1.30 160/17 OEL...

$164.95 USD

* GOOD NIKON E PLAN 100X OIL OBJECTIVE 100/1.25 OIL, 160/0.17

USA

* GOOD NIKON E PLAN 100X OIL...

$39.95 USD

* GOOD NIKON E PLAN 100X OIL...

$39.95 USD

Olympus SPlan 40x Microscope Objective 0.70 160/0.17 S-Plan Japan 40

USA

Olympus SPlan 40x Microscope...

$115.00 USD

Olympus SPlan 40x Microscope...

$115.00 USD

Carl Zeiss 3.2x/0.07 46 01 00-9904 3.2x Compound Microscope Objective 160/-

USA

Carl Zeiss 3.2x/0.07 46 01 00-9904...

$48.99 USD

Carl Zeiss 3.2x/0.07 46 01 00-9904...

$48.99 USD

Unitron 100X/1.25 Oil DM Phase Contrast Microscope Objective Lens 73885

USA

Unitron 100X/1.25 Oil DM Phase...

$39.00 USD

Unitron 100X/1.25 Oil DM Phase...

$39.00 USD

AmScope Achromatic Microscope Objectives : 4X, 10X, 40X Lot of 3 pieces

USA

AmScope Achromatic Microscope ...

$39.00 USD

AmScope Achromatic Microscope ...

$39.00 USD

Olympus SPlan Apo 20x / 0.70 160/0.17 Microscope Objective 20

USA

Olympus SPlan Apo 20x / 0.70...

$349.95 USD

Olympus SPlan Apo 20x / 0.70...

$349.95 USD

Mitutoyo 378-801 M Plan Apo 2 Microscope/Camera Lens, 2x, 0.055, F=200

USA

Mitutoyo 378-801 M Plan Apo 2...

$120.00 USD

Mitutoyo 378-801 M Plan Apo 2...

$120.00 USD

100X/1.25 DIN Achromatic Objective Lens for Compound Microscopes (Oil, Spring)

USA

100X/1.25 DIN Achromatic Objective...

$46.99 USD

100X/1.25 DIN Achromatic Objective...

$46.99 USD

Nikon Fluor 40x /.85 160/0.11-0.23 Microscope Objective

USA

Nikon Fluor 40x /.85 160/0.11-0.23 ...

$239.95 USD

Nikon Fluor 40x /.85 160/0.11-0.23 ...

$239.95 USD

Wild Heerbrugg 50X/0.85 POL Polarizing Microscope Objective Lens RMS

USA

Wild Heerbrugg 50X/0.85 POL...

$174.99 USD

Wild Heerbrugg 50X/0.85 POL...

$174.99 USD

Nikon BD Plan 100 0.90 Dry 210/0 Objective Industrial Commercial Lens ~FREE SHIP

USA

Nikon BD Plan 100 0.90 Dry 210/0...

$75.00 USD

Nikon BD Plan 100 0.90 Dry 210/0...

$75.00 USD

AmScope PA4X-INF 4X Infinity Plan Achromatic Microscope Objective

USA

AmScope PA4X-INF 4X Infinity Plan...

$27.60 USD

AmScope PA4X-INF 4X Infinity Plan...

$27.60 USD

Carl Zeiss Neofluar 16/0.40 160/-

USA

Carl Zeiss Neofluar 16/0.40 160/-

$53.90 USD

Carl Zeiss Neofluar 16/0.40 160/-

$53.90 USD

* AO/AMERICAN OPTICAL 100X OIL OBJECTIVE; ACHROMAT #1079 100/1.25, INF.

USA

* AO/AMERICAN OPTICAL 100X OIL...

$16.95 USD

* AO/AMERICAN OPTICAL 100X OIL...

$16.95 USD

Nikon CFN Plan 20X/0.50 Microscope Objective Lens 160mm Optiphot Labophot ++

USA

Nikon CFN Plan 20X/0.50 Microscope...

$139.00 USD

Nikon CFN Plan 20X/0.50 Microscope...

$139.00 USD

Bausch and Lomb Microscope Objective Lens 97X Phase Contrast Oil Immersion

USA

Bausch and Lomb Microscope Objective...

$24.00 USD

Bausch and Lomb Microscope Objective...

$24.00 USD

60X Achromatic Objective Lens for Compound Microscope

USA

60X Achromatic Objective Lens for...

$62.99 USD

60X Achromatic Objective Lens for...

$62.99 USD

Zeiss CP-ACHROMAT 100X/1,25 Oil ∞/0,17 Microscope Objective Lens; PN 44 09 80

USA

Zeiss CP-ACHROMAT 100X/1,25 Oil...

$80.00 USD

Zeiss CP-ACHROMAT 100X/1,25 Oil...

$80.00 USD

CARL ZEISS A-PLAN 40X/0.65 PH2 PHASE CONTRAST MICROSCOPE OBJECTIVE - 441051

USA

CARL ZEISS A-PLAN 40X/0.65 PH2 PHASE...

$124.95 USD

CARL ZEISS A-PLAN 40X/0.65 PH2 PHASE...

$124.95 USD

*NEW OLD STOCK* c.1914 FLATTERS & GARNETT "MERSOL" MICROSCOPE IMMERSION OIL

Australia

*NEW OLD STOCK* c.1914 FLATTERS &...

$35.00 AUD

*NEW OLD STOCK* c.1914 FLATTERS &...

$35.00 AUD

CARL ZEISS CP-ACHROMAT 40X/0.65 MICROSCOPE OBJECTIVE - 44 09 50

USA

CARL ZEISS CP-ACHROMAT 40X/0.65...

$55.95 USD

CARL ZEISS CP-ACHROMAT 40X/0.65...

$55.95 USD

Fisher AMG Plan 10X phase contrast Infinity Microscope Objective New

USA

Fisher AMG Plan 10X phase contrast...

$46.00 USD

Fisher AMG Plan 10X phase contrast...

$46.00 USD

AmScope 4X Plan Achromatic Infinity Metallurgical Objective Lens for Microscope

USA

AmScope 4X Plan Achromatic Infinity...

$26.99 USD

AmScope 4X Plan Achromatic Infinity...

$26.99 USD

Olympus SPlan 10x Microscope Objective (BH CH BH2 CH2 BHTU BHS) 160mm ~ S Plan

USA

Olympus SPlan 10x Microscope...

$79.00 USD

Olympus SPlan 10x Microscope...

$79.00 USD

* NIKON SC 100X OIL OBJECTIVE: 100/1.25, 0.17

USA

* NIKON SC 100X OIL OBJECTIVE:...

$34.95 USD

* NIKON SC 100X OIL OBJECTIVE:...

$34.95 USD