Feature: 1. STANDARD THREAD: 4X achromatic objective lens, standard RMS size thread interface, suitable for most professional biological microscopes in the market. 2. METAL MATERIAL: The objective lens is made of brass and stainless steel materials, chrome plating, corrosion and drop resistance, has a longer service life. 3. AUTO REBOUNDING: With a spring protection device, automatic rebounding when in contact with the cover glass during observation to prevent crushing the specimen. 4. COATING FILM LENS: This achromatic objective lens uses high transmittance coating film lens, which have a high refractive index to ensure brighter imaging. 5. REPLACEMENT PART: The objective lens has a compact size, making it easy to install on the microscope, and can directly replace old or damaged ones. Specification: Item Type: Objective Lens Material: Brass, Stainless Steel Use: International standard RMS size thread interface, suitable for most professional biological microscopes on the market Specification: 4X. Package List: 1 x Objective Lens1 x Storage Cylinder