DeLorme Earthmate PN-40 Waterproof Hiking GPS 32-channel STMicroelectronics Cartesio chipset; dual-core processor for blazing-fast performance 500 MB of available onboard Flash memory; support for high-capacity SD cards (SDHC) up to 32 GB 3-axis electronic compass; Barometric altimeter More detailed onboard base map data for the U.S. Fast USB 2.0 data transfers to in-device SD card(no external card reader required)