Solid secure four-holes-per-base steel bases for your X-Bolt bolt action rifle. The X design offers strength like no other. And it is a good thing. No removable base system locks your scope bases down more securely than the X-Lock system. Securely mounted optics are essential to the accuracy and precision of any rifle. To ensure the new X-Bolt has the most stable mount possible, it features an all new X-Lock scope mounting system that uses four screws per base, replacing the traditional 2-screw system. With the scope bases being secured at all four corners rather than only held at the center of the base, allowing for more accurate placement of the bases on the receiver. This revolutionary new X-Lock system holds the base tighter to the rifle than ever before.