The Glock Magazine is composed of a steel magazine body, a polymer floorplate and follower. The polymers are molded in the same color as the magazine itself. The floorplate and follower are also colored to match each caliber. For example, a 9mm magazine will have a blue polymer follower and floorplate while a 40 S&W magazine will have an orange follower and floorplate. In addition to offering greater impact resistance than aluminum, polymer is lighter than steel and it helps reduce overall weight of the magazine when empty which makes them easier to carry or put into a duty holster.