The Daniel Defense Vertical Grip is designed for superior ergonomics and control, featuring soft-touch rubber overmolding that enhances grip, whether wet or dry. Inside the grip, you'll find a Dual O-Ring, water-tight storage compartment, perfect for securely holding small parts or essentials. This ultra-lightweight vertical grip mounts easily and securely onto 1913 picatinny rail systems, offering a simple yet durable attachment method. Please note, it is not compatible with KeyMod or M-LOK rail systems. Whether for tactical use or range time, this grip provides added functionality and reliability in a compact, streamlined design.