Product Description: The aluminum alloy housing is precision machined, stable and durable for long-term use. This is a 100X objective lens for biological microscopes. It can eliminate unwanted reflections and increase contrast. Provides high-quality observation without additional chromatic aberration, making the image clearer. The length of the objective lens is 36.5 mm, easy to use. Material: Aluminum Alloy + Optical Lens Color: As pictures show Magnification: 100X NA: 1.25 Conjugate Distance: 185 Thickness of Cover Glass: 0.17 mm Length of Objective Lens: 36.5 mm Mounting Size: 20.2 mm (Standard RMS Thread) Package Weight: 46 g Package includes: 1 x Microscope Objective Lens Note! Please allow 0-2 mm error due to manual measurement. Make sure you don't mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you If you really care about these details, please DO NOT order. 185 Conjugate Distance The conjugate distance of 185 is the distance between the object plane and the image plane of the objective lens in the microscopy system. Optical Lens It can eliminate unwanted reflections and increase contrast, providing high-quality observation without additional chromatic aberration, making the image clearer. Aluminum Alloy Housing The outer housing of the objective lens is made of aluminum alloy and is durable. The aluminum alloy is corrosion-resistant and does not rust when exposed to water or chemicals. It can be used in the laboratory. The surface is finely polished, and the touch is smooth and comfortable. Standard RMS Thread Standard RMS thread, 20.2 mm mounting size, please confirm the size of your microscope thread before purchasing.