Features: 3X magnification with a 1.25-inch interface increases the magnification of any 1.25-inch eyepiece, also offers a comfortable viewing effect. 3X High power magnification: more detailed at the star, moon and other celestial bodies. Fully multi-coated optical lens: high transmittance to achive clear and sharp views. Providing more magnification without reducing the exit hole on the eyepiece and keeping a comfortable observation with wide view. Easy to use: simply insert the eyepiece into Barlow lens, and then insert the Barlow lens into the scope. Specification: Color: black Material: Optical glass + Metal Magnification factor: 3X Interface: approx. 1.25inch (31.7mm) Length: 65mm/2.6in Weight: approx. 75g Package List: 1 * Barlow Lens 3X 13X magnification with a 1.25-inch interface increases the magnification of any 1.25-inch eyepiece, also offers a comfortable viewing effect. 23X High power magnification: more detailed at the star, moon and other celestial bodies. 3Fully multi-coated optical lens: high transmittance to achive clear and sharp views. 4Providing more magnification without reducing the exit hole on the eyepiece and keeping a comfortable observation with wide view. 5Easy to use: simply insert the eyepiece into Barlow lens, and then insert the Barlow lens into the scope.