Warne Mag Ext S&w M&p 9/40 +5/4 BlkWarne Handgun Magazine Extensions are available in both increased capacity models, and zero capacity models for 10 round capacity limits. These extensions feature an ergonomic shape that allows for better insertion, and finger grooves, allowing the magazine to be stripped from the handgun if needed. Features : Fits S&W M&P 9 40 Machined from 6061 T6 aluminum billet Type 2 hardcoat anodize finish for abrasion and corrosion resistance Torx head screw