The Accurate Mag Short Action Magazine Extension is the ideal solution for extending the capacity of your AICS pattern magazine. These extensions add 4 round capacity for .308 and 6.5 Creedmoor and 2 round capacity for .300 WSM and 6.5 PRC and a positive grip for mag extraction. It is easily installed by sliding off the old floorplate, depressing the spring, and sliding on the extension. Then screw on the backplate and it's ready to go. These extensions are compatible with any steel AICS pattern magazine, excluding the Accurate Mag .223 magazine.