The ALPS Mountaineering Bite Valve features easy one-handed operation with a high flow valve for quick hydration. Compatible with 1/4" drink tubes on packs with 1" or 3/4" wide straps, the magnet base keeps the drink tube in place when not in use. Features: - High flow 360deg bite valve - Convenient one-handed shut-off/turn-on - Magnet keeps drink tube in place until needed - Magnet base fits 1" or 3/4" wide pack straps - Fits 1/4" ID drink tube