Usage Tips:40X 185 Biological Microscope Achromatic Objectives Lens 160/0.17 Features: 1. Aluminum Alloy shell is precision machined, stable and durable for long time use. 2. This is a 40X achromatic objective lens for biological microscope. 3. It can eliminate unwanted reflections and increase contrast. 4. Offers observation without additional chromatic aberration, make image more clear. 5. The Length of the objective lens is 37.8mm, easy e. Specification: Item Type: Achromatic Objectives Lens Material: Aluminum Alloy + Optical Lens Color: As Pictures Show Magnification: 40X Tube Length: 160mm / 6.3inch Conjugate Distance: 185 Cover-glass Thickness: 0.17mm   Objective Lens Length: 37.8mm Mounting Size: 20mm（Standard RMS Thread) Item Size: 5 * 5 * 5cm / 2.0 * 2.0 * 2.0inch Package Weight: Approx. 62g Package List: 1 * Achromatic Objectives Lens