"Critical for long-range accuracy, the Wheeler Anti-Cant Indicator helps you keep your high performance scope and gun on target. Even more important on today's ""drop compensating"" rifle scopes, this easy-to-use anti-cant indicator helps you ensure your rifle is near perfectly vertical before you squeeze the trigger. Easy to view from the shooting position, this convenient indicator folds out of the way when not in use. Machined, anodized-aluminum construction. Cant indicator keeps you on target Helps you ensure rifle and scope are vertical before shooting Easy to view from shooting position Folds when not in use Machined anodized-aluminum construction"