17round magazine (Glock 17) - Glock OEM®17 rds in 9 mmP Each GLOCK magazine is constructed from a hardened steel insert encased in high tech polymer to protect the magazine and prevent deformation, even when dropped from a great height. The high quality spring and follower ensure reliable feeding from the first round fed by a fully compressed spring down to the last shot. Features Constructed of hardened metal encased in durable polymer Viewing windows for visual confirmation Double stack