The GPSMAP 60CSx Portable Navigator is one of most popular models for outdoor and marine use. It contains a removable microSD card for detailed mapping memory and a waterproof, rugged housing. The microSD card slot is located inside the waterproof battery compartment. It features a new, highly sensitive GPS receiver that acquires satellites faster and lets users track their location in challenging conditions, such as heavy foliage or deep canyons. Owners of new x-series handhelds can also purchase new microSD cards that are pre-loaded with MapSource Topo and inland lake maps, BlueChart marine cartography, and City Navigator street maps.