One of the big drawbacks of a Systema PTW rifle is that they chose to make the stock tube in a civilian size, which meant that you could not install Milspec sized stocks onto it. Say goodbye to that problem with this new RWC Milspec Size stock tube designed for the Systema PTW. Just install it and you are open to a world of milspec stock options!
*mil spec tube - 1.14
commerical stock- 1.17"
As shown in the photos, the stock tube has the grooves already cut in to allow the ECU wires to pass through. No additional modification necessary.
While you're at it, we highly recommend you also purchase the Airsoft Surgeon Miniaturized ECU, which fits inside the stock tube. This mini size one replaces the stock ECU, which actually takes up half the inner stock tube. By installing a smaller ECU, you can free up precious space to store a LiPO battery, and thus free yourself from relying on a CRANE stock for battery storage. If you intend to install MILSPEC sized stocks from Magpul or other manufacturers (which have no storage compartments for batteries), then installing the Airsoft Surgeon Miniaturized ECU is a must.