Tactical rail allows you to add standard accessories such as lasers, flashlights, fore grips and red dots...the upgrade options are now limitless. Most Picatinny and Weaver accessories will work on our rail mounts. FOR Magnum 1.5mm wall MODELS ONLY It best you order these once you have your blowgun in hand to make sure you order the correct size TO MAKE SURE YOU ORDER THE CORRECT COMPARE YOUR BARREL TO THE SIZE OF A PENNY AND A NICKEL, IF THE BARREL IS LARGER THAN A PENNY YOU HAVE A 2.5MM WALL BLOWGUN. IF YOUR TUBE IS SMALLER THAN A NICKEL YOU THEN HAVE A 1.5MM WALL BLOWGUN