Made for right-hand firearms this DNZ Scope Mount - Browning X-Bolt LA has base screws of 6-48 X 1/4 inch long and rings screws that are 6-40 X 5/8 inch long. This mount is designed for both short and long action and is precision machined from top-grade aluminum. This mount is custom made for a perfect fit and will align perfectly with the receiver of a rifle. There are no moving parts between the firearm and the scope and this mount is 67% lighter than conventional mounts.