STX Cell II Lacrosse Shoulder Pads - Men's The Cell II Shoulder Pad from STX is equipped wtih isoBLOX technology to protect while keeping your complete range-of-motion through the chest, back and shoulders. A simplified design includes fewer parts for fewer distractions. The low-profile shoulder cap design is also built with the isoBLOX technology for added flexibility. Includes adjustable/removable bicep pads within the high-performance materials. Size M is designed for players who weigh 91-140 pounds. Size L is designed for players who weigh over 140 pounds.