Kel-Tec P11043 Magazine Extension made of Polymer with Black Finish & Adds 1 Extra Round for 40 S&W Kel-Tec P-11 15rd Magazines This Magazine extension adds 1 extra round to your P-11 15rd magazine. ADDITIONAL INFORMATION SKU 25998-c3NvdXRo UPC 640832001037 Weight 0.08 LBS Height 0.10 (in) Width 4.80 (in) Depth 6.00 (in) Caliber 40 S&W Capacity 1 Finish Black Model Magazine Extension Material Polymer Type Magazine Extension Model Fit P-11 Brand Fit Kel-Tec Capacity 10