Extension tube for eye telescope or 1.25 inch filterMade of aluminum, black anodizedThis 1.25 inch extension tube adds some length to the light path of your telescope, and provides an extra" rear trip "for short-range ground visionThe brass compression ring design holds your lenses or accessories securelyThread pitch: M28.5 * 0.6 (for standard 1.25 inch filter)Model Number: Extender TubeExtender Tube: for telescopeLength:56mmSize:M28.5*0.6Material:metalcolour:blackPackage Contents:1 * Telescope ExtenderOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.