This picatinny rail attaches to your standard handguard or Magpul handguard. If you like the look of your standard handguard or don't want to get a quadrail, this rail allows you to mount accessories underneath your standard handguard. Ideal for a forward grip, angled foregrip, bipod, or a flashlight. It measures 5" length, and has 9 slots. Attaches and screws in three different locations to allow for a secure, tight fit.