The Pro X Series Quick-Connect Fat Sacs have raised the bar in boat weighting systems. Similar to river rafting material, the new Valmex material is so strong that punctures and abrasions are virtually a thing of the past. Tough strong seams are welded and taped to prevent common failures. The quick-connect valve system lets you pump water 10 times faster than the old water bed system. 48″ x 12″ x 12″.