Pachmayr Grip Extender greatly increases your control and shooting comfort when added to popular compact and sub-compact handguns. The extension perfectly matches the shape and texture of the handgun. It is easy to install and is made of tough, high strength polymer that stands up to the roughest handling. In addition, the Extender comes in a pack of two. This model is compatible with your Glock 26/27/33/39 and adds 2-rounds. Converts 27/33 to 11 rounds, 26 to 13 rounds