Alpen Apex XP 6-24x50mm SF Riflescope is a superb 6-24x variable magnification rifle scope with a 30mm tube, that's loaded up with Xtreme performance features. It features fast focus eyepieces and a generous amount of eye relief. This waterproof riflescope is sealed tight to be fog-proof, with a durable shockproof body and optical system that is shock-tested to 1000 Gs of magnum force. It features fully multi-coated optics for maximum light transmission and optical clarity. The Alpen XP 6-24x50mm SF 30mm Riflescope also has zero-set low profile adjustment knobs for windage and elevation.