JL Billet Internal CA Magazine Lock Upgrade Black. See video for installation details. Specifications for JL Billet Internal CA Magazine Lock Upgrade: Manufacturer: JL Billet Gun Make: DPMS Gun Model: DPMS LR-308 Color: Black Gun Type: Rifle Weight: 0.1 lb Country of Origin: USA Features of JL Billet Internal CA Magazine Lock Upgrade AR15 California Compliant Mag release AR Maglock quick install to convert ARs for Cali Compliance Package Contents: JL Billet Internal CA Magazine Lock Upgrade What firearm models does the manufacturer say JL Billet Internal CA Magazine Lock Upgrade is compatible with? The manufacturer says that JL Billet Internal CA Magazine Lock Upgrade is compatible with DPMS LR-308JL Billet JLB-CCK: Internal CA Magazine Lock Upgrade Black