This Telescope bag is constructed from 60-gauge heavy-duty PVC materials for the utmost in durability. Sonic welded seams and fill drain ports ensure it withstands long-lasting use. The Telecope bag includes one 1-1/2" diameter fill port, one 1" diameter fill/vent port, and two 1" diameter drain ports. Bag must be filled using Eight.3 ballast pumps from Ronix. 35"L x 35"W x 9"H. Sonic welded seams Ideal for creating your perfect wake | Ronix Eight.3 Telescope Square Shape Ballast Bag, 400 lbs