ProMag S&W 910/915/459/5900 Magazine 9mm Blued Steel 20/rd

The ProMag Smith & Wesson 910/915/459/5900 Magazine in 9mm Blued Steel with 20-round capacity is a purpose-built extended magazine for the S&W semi-automatic pistol lineup. Constructed from heat-treated blued steel with a follower lock-plate and base-plate molded from proprietary DuPont Zytel-based black polymer, this magazine delivers reliable feeding and retention for duty, training, and competition use. The chrome-silicon spring is heat-treated for consistent performance across thousands of cycles.

The 20-round double-stack configuration extends magazine capacity beyond factory standard while maintaining a profile compatible with standard S&W 910, 915, 459, and 5900 series frames. The blued-steel construction resists corrosion in typical duty environments, while the polymer base and follower absorb impact stress and prevent binding. Proper indexing and witness holes allow visual round-count verification. The heat-treated spring maintains tension integrity even after extended storage or heavy use cycles.

This magazine suits law enforcement officers, competitive shooters, and civilian operators running S&W third-generation or newer-generation platforms who need increased ammunition capacity on a single magazine. Range training sessions benefit from fewer reloads, while duty rotation shooters appreciate the extended payload for qualification and qualification-style scenarios. Aftermarket extended magazines address the original equipment manufacturer's capacity limitations without requiring pistol modification.

Third-party magazines for the S&W 910/915/459/5900 series remain widely used in civilian and training environments where duty limitations do not apply. The ProMag SMI-A2 competes in the mid-range priced segment, offering capacity expansion at a fraction of genuine S&W magazines while maintaining basic reliability standards expected of modern magazine engineering.