The new Sky-Watcher 90° Polar Scope Eyepiece now makes polar aligning your mount so much easier! The eyepiece sleeve securely clamps over the standard polar scope eyepiece using three non-marring, plastic-tipped, knurled metal thumbscrews. This is far superior method of clamping compared to similar looking products on the market that use only one clamping screw and more reliable than those using a brass compression ring, which can be problematic. The internal diameter of the eyepiece clamping sleeve is 30.1mm. For optimum positioning, the eyepiece can rotate 360º around its axis in click-stops. The eyepiece can be switched between 1x and 2x magnifications. For viewing comfort, the eyepiece is fitted with a soft fold-down rubber eyecup. An adjustment of +/-4 dioptres is provided to adjust to your eyesight. Suitable for fitting to the polar scopes of Sky-Watcher EQ3, EQ5, AZ-EQ5, HEQ5, EQ6, EQ6-R, AZ-EQ6, SAM & STAR ADVENTURER mounts as well as many mounts of other brands.