Color: 0.965 to 1.25 InchThis is a very high quality anodized aluminum adapter that has filter threads at the bottom for 0.965" telescope filters? It also has an internal brass ring that the set screw hits to hold your 1.25" eyepiece inside? This eliminates marks on your eyepiece barrel? Nice large thumbscrew that is easy to turn even in very cold conditions or with gloves on?