Express: 
This lithium-Ion battery pack is ideal for extended outings with your Montana. Keep with you as an extra power source or buy as a replacement. The Montana range of handhelds is designed for use on foot, on the road and on the water and for a variety of adventures. Montana is rugged, waterproof and tough capable of withstanding all the mud and grit you can throw at it. It features a high-sensitivity GPS receiver with HotFix for optimal positioning. It has a bright 4-inch colour touchscreen display with dual orientation and perfect readability under any light conditions. Wherever you take it, it's built to withstand the elements. With a vast 4" sunlight-readable touchscreen that offers crystal clear enhanced colours, dual orientation display and high sensitivity HotFix positioning to track your location, it's easy to see where you are at all times. Both durable and waterproof, Montana 600 is built to withstand the elements. Use with The Montana with City Navigator NT or Garmin GB Discoverer maps for spoken, turn-by-turn driving directions. Wherever you think you might take Montana, it has the mapping and mounts to get you there But you don't want your battery to run out while on your adventure - especially on a long trek in the wilderness. The lithium-Ion battery pack gives you that added security and back-up.
