The SME Brass Catcher features a swing-open design which allows for convenient chamber access. It also features a heat-resistant mesh bag with an internal cage to maintain the shape. Hook & loop attachment for use on bolt-action and semi-automatic rifls. It mounts to any rifl with a flat top or picatinny rail hand guard and it's compatible with most AR/LR-308 models. Mfg: Shooting Made Easy