Orion 5123 1.25-Inch Telescope Eyepiece Extension Tube Versatile extension adapter for 1.25" telescope eyepieces and accessories adds 2" of extension Provides extra focuser back travel which is often needed for short-range terrestrial viewing or astrophotographic applications Includes two thumbscrews for securing inserted telescope eyepieces or accessories Threaded for use with 1.25" telescope eyepiece filters Made of anodized machined aluminum