Does not affect Tubes quick release function Multiple ballistic protection levels available Designed for Siege-R Optimized or Strandhogg carriers Run as a system or individual components Components attach to a vest (Sold Separately). The M.A.S.S. is an excellent alternative to traditional, less thought out systems. it is time to get all you can functionally employ. M.A.S.S. is available to provide additional protection to the neck/throat region, shoulders, and upper arms. The M.A.S.S Shoulder Pads are sold as a set of 2