yep thats all it does, just puts your scope on at a slant so its slightly pointed down, then when you sight in your adjustment is off centered giving you 20 moa of additional up. My rifle sighted dead on at 300 yards is about 2.25" high at 100, my scope is 2.1" above center of bore, so with a 300 yard zero I'm never more than 3 inches high from 0-100, just hold lower third on the shoulder.here is a source for a 20 moa base
www.seekinsprecision.com RR