Salmon River Solutions SRS Arca + Picatinny Rail Black. The Arca + pic enables someone to have a single rail to run a bipod and a tripod off. Made from 7075 aluminum it is 4.7 OAL and has a bolt spacing of 1.5 to 3.5. These come with a sling stud hole and a QD cup. We like to use these at the fore end for shots at a steep incline / decline where you utilize the tripod to support the gun instead of a bipod. You get 1.7 of ARCA rail and 2 of pic rail. Weight is 1.0 oz. Specifications for Salmon River Solutions SRS Arca + Picatinny Rail: Manufacturer: Salmon River Solutions Color: Black Finish: Anodized Fabric/Material: 7075 Aluminum Gun Rail: Arca Picatinny Gun Type: Rifle Features of Salmon River Solutions SRS Arca + Picatinny Rail Arca Picatinny QD Cup Sling Stud Package Contents: Salmon River Solutions SRS Arca + Picatinny Rail M-Lok Fasteners 10-32 Fasteners Salmon River Solutions 1111: SRS Arca + Picatinny Rail Black