**If the thought of being without your cell phone, PDA, camera or other valuables when you`re out on the water makes you shudder, you need an award winning DRY PAK! DRY PAKs hermetically seal out water, sand and dust. Simply twist the knobs to open; twist back down to seal. It`s that simple. If you drop it in water, it will float and your belongings are protected. **Although only a few popular uses and activities are identified for each case, it`s highly likely that you`ll find other applications for your DRY PAK. If you have a specific item that you want to protect, measure it first and check the maximum circumference dimensions that we provide. **What is TPU? Many of the clear DRY PAK items are constructed of a hi-tech thermo-plastic-polyurethane. It`s approximately 10 times stronger than vinyl and has incredible resisitance to hot and cold temperatures. Sounds transmit through TPU with less than 5% loss of volume, making it the perfect choice for phone and VHF radio cases. Optically clear materials are used for camera and camcorder cases. SPECIFICATIONS: 4"W x 4"L. *Blue "alligator" embossed TPU front, clear TPU back. *Adjustable neck lanyard included. *Yellow sealing clip for high visibility. *For beach, pool, boating, airports, water parks, hiking, snorkelling. Holds ID, cash, credit cards, keys, pagers. Maximum circumference: 7 1/4".