ProMag Sig Sauer P229 Magazine .40 S&W / .357 Sig Blued Steel 12/rd

A 12-rd magazine for the Sig Sauer P229 pistol in either .40S&W or .357Sig. Constructed from heat-treated blued-steel with a follower lock-plate and base-plate molded from a proprietary DuPont Zytel based black polymer; and using a spring wound from Chrome-silicon wire and heat-treated for strength and reliability.