Focusing at high magnification with a standard rack-and-pinion focuser can be a real challenge. The focuser action is coarse, making it hard to nail the exact focus point. This precision-machined adapter makes fine focusing a breeze. It replaces the 2″-to-1.25″ eyepiece adapter in telescopes equipped with a 2″ focuser, allowing very fine helical focusing with just a feather touch. Critical focus is easier to achieve, and images stay steadier. The Orion Helical Fine-Focusing Adapter features dual rubber grip rings and setscrew lock. Works with 1.25″ eyepieces. Requires at least 9mm inward focus travel.