Improve Your Accuracy with a SightRight Training Insert Cue Extender! You don't have to wait to start experimenting with SightRight - or get rid of your favorite cue. Now any cue can give you the benefit of SightRight - in seconds. Just slip one of these 3.75'' Maple extenders between your cue butt and shaft, and away you go. SightRight improves your game by helping develop a consistent pre-shot routine using a simple two-line alignment system, removes the guesswork surrounding eye dominance and aiming, perfects your aim by focusing on utilizing your individual eye dominance, creates consistently aligned technique, carrying through to accurate cue action, improves accuracy across your entire game, including rest play and escaping snookers, and gives specific practice routines to hone your new skills.