Feature: Made of high quality optical materials to ensure excellent optical performance. The surface of the lens has a precise coating, high light transmission, wear resistance, and effective protection of the lens. Good light transmission, effectively reducing the unnecessary power loss of laser. Products are widely used in laser engraving machines, laser cutting machines, etc. The focal length is 50.8mm and the diameter is 20mm. Please pay attention when purchasing. Specification: Diameter: 20mm Focal length: 50.8mm Package list: 1 * Laser Lens Note: The actual product color may deviate from the photo due to light. There may be a slight deviation in the measurement of product. Package List 1Made of high quality optical materials to ensure excellent optical performance. 2The surface of the lens has a precise coating, high light transmission, wear resistance, and effective protection of the lens. 3Good light transmission, effectively reducing the unnecessary power loss of laser. 4Products are widely used in laser engraving machines, laser cutting machines, etc. 5The focal length is 50.8mm and the diameter is 20mm. Please pay attention when purchasing.