Easily attachable and removeable gauge port to monitor pressure easily. This 360 swivel gauge adapter for the DM/PM 8. The TechT L7 2011 Proto Rail Bolt utilizes the same technology as the rest of our L7 Line of bolt systems. It delivers unparalleled performance by producing lower dwells and operating pressures that yield unbelievable accuracy and efficiency. The L7 Bolt for the 2011 Proto Rail is constructed using 100 percent aircraft grade aluminum. The bolt itself only weighs in at 11.3 Grams, as oppose to the stock which weighs 26.0! The bolt produces virtually no kick, which helps players hit targets more consistently; which at higher rates of fireis a must. Get more eliminations- get the TechT L7 2011 Proto Rail/Reflex Bolt Upgrade!