High-sensitivity GPS receiver with HotFix for improved performance and reception USB interface Waterproof standard Unit-to-unit wireless data transfer capabilities for waypoints, routes and tracks Electronic compass and barometric altimeter Rugged, lightweight Up to 18 hours of battery life, 2 AAA; NiMH or Lithium recommended Foretrex 401, USB cable, expander strap, owner's manual on disk and quick start manual