This is part of LED Lighting a Microscope, MK3
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Seller: gracelightled 1set Optical Glass Lens+ Reflector for 10W High Power Led light chip Square LED 331175203600 $2.40 (and 331151323878, 10 set for $27.00) Glass Len Size: Dia: 44 mm* H19 mm Holder Size: Square 18mm/ Round 56.5mm Tol:+/-0.2mm Material: High Temperature Resistance Borosilicate Glass Light transmittance:96% Lighting Angle: 60-90 Degree, 120 Degree. Pls left message for the degree you require, or we sent in random.. Different Degree Lens and Holders may have size different, But all for 10W High Power Led Chips.
Seller: tubelight 44mm Lens + Reflector Collimator + Fixed bracket For 10w 50W 100W high power LED 371181913754 US $3.76 Beam Angle: 60-80 degree. Light transmittance: 98%. Lens material: Glass
90-120°led Lens + Reflector Collimator for 20W 30W 50W 70W 100W High power led 331508835075 $2.60 gracelightled
90-120°led Lens + Reflector Collimator + Fixed bracket 20W 30W 50W 70W 100W LED 231128140496 $3.40 gracelightled
44mm Lens + Reflector Collimator + Fixed bracket For 20W 30W 50W 70W 100W LED 331059364770 $3.40 gracelightled
77mm Lens + 82mm Reflector Collimator Base + Fixed bracket For 20W-100W 50W LED 331199211801 $10.99