Available for In-Store Pick Up One new Magpul MS4 Dual QD GEN2 Multi-Mission Sling System, Gray. This sling is built around the MS1 sling, is set up for QD-style front and rear sling attachment points, easy one-handed tension adjustment, melonite finished steel, manganese-phosphate finished steel with reinforced polymer hardware, custom snag-free high durability 1 1/4" webbing and is optimized for use with the ASAP-QD and RSA-QD or MSA-QD.