The TAL 4 Tactical Vertical Foregrip is designed for the Standard (underside) Picatinny Rail.The (Optional) Double Sided Pressure Activating Flashlight Switch, provides convenient control for your Tactical Light making the TAL 4 an ideal accessory for your tactical upgrade. Advantages: Quality Non-Slip Design Double Side Pressure Switch Housing Internal Water Resistant Battery Compartment Both Quick Release Mechanism and a Secure Bolt Locking System Available Spring Based Locking Mechanism Allows Silent Batteries Storage Designed to Fit a Standard Picatinny Rail Durable, Hardwearing & Lightweight Polymer Construction User Installed-No Modification or Gunsmith Required