Callfire@10" Long Pica-tinny 20mm Base System Rifle Base Mount 25 Slots 257mmx20mm This 10" pica-tinny accepts all wea-ver standard rings. These are very high quality rail for you rifle, and make an excellent upgrade. Length 10" / 257mm Material High Quality 6061 Aluminum Package Includes 3 Screws, 1X Alloy Key