LEUPOLD 2 Piece Bases Standard American Centrefire Finish:Matte 1 The Rear height is

1 The Rear height is measured from the top of the action to the top of the rail

3" Chamber (410ga)

an all coil spring mechanism

22 WMR and 17 HMR

True 1x on the low end is complimented by an ultra-forgiving eyebox with generous eye relief for a heads-up-display-like sight picture and a daylight bright illuminated centre dot in the reticle for extremely fast target acquisition in close quarters

LEUPOLD 2 Piece Bases Standard American Centrefire Finish:Matte 1 The Rear height isLeupold steel Standard (STD) rings and bases are the most versatile of any mounting system we offer. This specific model fits a Ruger American SA and is the perfect choice for standard calibers less than . 300 Win. Mag. STD rings come in five different heights and are precision engineered to match up with STD 1 piece or 2 piece bases. The front dovetail ring pivots, allowing for lateral adjustment using the rear windage screws while bore sighting.