PTS Enhanced Polymer Stock. this is the next generation fo polymer stocks from PTS. The stock is manufactured from authentic Dupont Zytel polymer for superior wear and damage resistance. The stock features dual fixed side compartments for battery storage for all your power needs. The side compartments are approximately 20x15 MM and are large enough to handle most 9.6v nun-chuck batteries as well as most stick and butterfly type lipos. This awesome stock also features two QD Sling points.