Daniel Defense's Vertical Foregrip (Picatinny)" updated in 2014" now includes soft touch rubber overmolding for enhanced grip" wet or dry. Inside the grip is a Dual O-Ring" water tight storage compartment capable of storing small parts. This vertical grip is extremely lightweight and utilizes a simple yet durable mounting method for 1913 picatinny rail systems. Not Compatible with KeyMod or M-Lok rail systems.