The A5 Combo Kit features a longer receiver extension, longer housing, a specially weighted buffer and includes the M16A2 buffer spring. The smoother function and constant spring rate of the M16A2 buffer spring increases accuracy, reliability and performance. The A5 Combo Kit is an excellent choice for addition to any AR platform but is a notably superb upgrade for piston systems. Many piston systems suffer from over-gassed operation and excessive carrier velocities which, both of which can lead to an unreliable firearm and a decrease in accuracy. The A5 system has been proven to tame such problematic tendencies and often increases the reliability and accuracy of the weapon. The A5 Modstock (EMOD) features a wider and longer butt with strike plate, removable and waterproof side compartments with storage for four CR123 or three AA batteries and another weatherproof compartment on the clubfoot that holds two AA batteries or other small items. Includes the VLTOR A5H2 buffer weighing 5....