Designed specifically for use in Glock 17 (Gen5), Glock 17 MOS (Gen5) and Glock 34 MOS (Gen5) pistols, the LMS-G5-17 replaces Glock's factory spring guide assembly with a high intensity red laser sighting system for advanced target acquisition. Easily user installed without the need for gunsmithing or special tools, the Guide Rod Laser is constructed with rugged, precision components including aircraft-grade. Automatic time-out after 10 minutes prevents inadvertent battery drain.