Kel-Tec P-11 Magazine Extension .40 S&W 1 Round Black 1 Pack Polymer 1RD. The magazine may be loaded with the extension installed or in a magazine adapter but the sleeve is designed to fit standard magazine flush with the body of the pistol when in use. Most of the time an adapter is installed at the factory to extend the magazines but this can be done if the owner really wants to load the mag with a round after the last round but before the mag falls to the ground. This will also allow the shooter to load a wider variety of rounds in the magazine which can be critical in some situations such as shooting from a prone position or needing to load the magazine while in the crouch stance position. The magazine may have to be returned to the gunsmith for damage to either the extended or the sleeve due to the magazine being in a forward grip stance position. Specifications for Kel-Tec P-11 .40 S&W 1 Round Magazine Extension: Manufacturer: Kel-Tec Color: Black Fabric/Material: Rubber Magazine Capacity: 1 Round Caliber: .40 S&W Package Contents: Kel-Tec P-11 .40 S&W 1 Round Magazine Extension The Kel-Tec P-11 Mag Extension For S&w 59 Series Magazines is a quality addition to the Kel-Tec lineup. For more great deals on Pistol Magazine Extensions by Kel-Tec please browse our Kel Tec Weapon Accessories page. Kel-Tec P11043-1RD: P-11 Magazine Extension .40 S&W 1 Round Black 1 Pack Polymer