1) Fits for AR15 / M4 / M16 standard barrel, 19mm / 0.75 " Diameter and gas tube, 2 screws clamped
2) Allow to insert within free floating quad rail hand guard when take off all rail
3) 4 rail Bases on top, bottom and both side , 1.8" length
4) Precision Machined Out of Premium 6061 Aircraft Aluminum
5) Two pieces detachable Rails , 4 screws and wrenches included,
