TriMag connects three factory magazines standard to a Ruger 10/22 semiautomatic rifle. TriMag has become a standard accessory for avid 10/22 owners. Our design is unique in the way magazines are clamped together with no modifications to the original magazine, or use of glue or adhesives. Ours can be taken apart at any time and a magazine replaced or serviced. The shape of TriMag doesn???t interfere with your forearm when firing as extended magazines are famous for. Bench firing is more convenient - the shooter doesn???t have to move out of position to change magazines. It uses standard 10 round factory Ruger magazines, the most prolific, dependable, and popular magazine on the market. It supports the rifle in an upright position when inserted.