The purple Dri Cat Neck it Waterproof Case with Lanyard for iPhone 4/4S from EK USA is a silicone and polycarbonate shell submersible to 18'. The case clamps shut and is sealed with an interior o-ring gasket. Make or receive calls while you're in the water or just listen to music. The removable lanyard has a quick-release. It should be noted that you cannot use waterproof headphones while in the water since all the ports on the case are sealed.