Masterpiece Arms have developed a California-Legal version of their Mac-10-patterned carbines. The Defender Carbine models MPA1SST, MPA20SST and MPA9300SST now include a magazine lock device that will prevent the magazine from being removed without a tool, thereby making it Cali-Legal.

45 ACP Side Cocking Carbine Rifle with Scope Mount and 16″ Threaded Barrel (Standard Model, Not Cali-Legal)

No word if pricing for Cali-legal models is the same as the regular models.