• EASY SELF FILL / LEAK PROOF SEAL – Simple roll top hook and loop closure opens wide for easy fill and closes quickly and securely. Tall roll top gives a leak proof seal to keep your boat clean.
• FLEXIBLE FILL OPTIONS - Fill with rocks, gravel, sand, steel pellets, or whatever else you have handy. A sand/gravel mix will yield about 45 lbs per bag. Please note, these ballast bags come empty.
• FITS IN SMALL SPACES - Easily stows away in lockers, under seat cushions, or anywhere you've got a little empty space. Solid fill materials are more dense than water making ROC SAC great for tight spaces. A filled Roc Sac is about 14" x 12" x 3".
• PREMIUM DURABLE MATERIALS – Made with ultra-tough 22oz PVC coated polyester fabric (1000X1300D). Fabric is waterproof and UV resistant. Heat welded seams are strong and water tight. Built to last.
• VERSATILE APPLICATIONS – Great for boosting your wakesurfing wave and so much more. Anchor your jet ski, secure your tent, balance your small watercraft, or secure cantilever patio umbrellas, patio furniture, pool covers, trampolines, or almost anything you want to stay put.