STX Cell II Lacrosse Shoulder Pad Liner - Men's The Cell II Shoulder Pad Liner is created with STX isoBLOX technology for maximum protection and a complete range-of-motion in the chest, back and shoulders. The simplified, low-profile design keeps this liner lightweight and extremely flexible. A combination of unique textures and materials make for a high performance look. Size M is designed for players who weigh 91-140 pounds. Size L is designed for players who weigh over 140 pounds.