The 2" Cheshire Autocollimator from Farpoint is a rigid and durable collimation tool for final alignment of large-aperture optics. This device is compatible with all 2-inch eyepiece/diagonal optical tubes and should be used during the final step of optical alignment. Successful use of this device requires the optical instrument to be aligned with basic collimation tools such as a laser or sight tube and a Cheshire. The 2" Autocollimator is utilized for precise, final alignment adjustments.