1Easy to Use: Fits 25in focusers, simply cover the telescope, remove the diagonal, and place the eyepiece directly in the focuser. 2High Accuracy: The collimator of the reflector telescope has a 45 degree plate to improve visual accuracy. 3Good Performance: Accurate collimation is essential for high power observations, stars become more like pinpoints of light, and details of planets and the Moon are enhanced. 4Prime Material: The product is made of aluminum alloy with crosshairs on the bottom for quick and accurate centering of optical lenses. 5Application: This collimating eyepiece can be used to accurately collimate Newtonian and SCT for better image quality.1 xCollimating Cheshire Eyepiece1 x Dust CoverItem Type: Collimating Cheshire EyepieceWeight: 195g / 6.9ozMaterial: Aluminum, Optical GlassInterface Size: 1.25in (31.7mm)