1、BRASS, STAINLESS STEEL MATERIAL: Made of premium brass and stainless steel material, these lens are anti corrosion and anti drop, exquisite and durable, with chrome plated accuracy material on the shell. 2、SPRING PROTECTION DEVICE: When observing, contact with the cover glass, the lens can automatically rebound, protecting the lens from damaging the specimen. 3、RMS SIZE: The thread interface size is an international standard RMS size, and most professional biological microscopes on the market can be used. 4、CLEARER IMAGE: These lens are coated with strong transmittance film, with high refractive index and brighter imaging. 5、4 LENS: There are 4 pcs lens, 4X 10X 40X 100X, you can use them respectively to meet your different needs. Item Type: Achromatic Objective Material: Brass, Stainless Steel Application: Widely used for the thread interface size is an international standard RMS size, and most professional biological microscopes on the market can be used. Specification: 4X 10X 40X 100X 4 x Lens 4 x Storage Tube