Product Info NameUSGlobalSat GPS ReceiverModel III 20-Channel SDIO GPS Receiver with 512mb of memory built-in.Features: 1. SiRF Star III high performance and low power consumption chipset. 2. SD-502 has a built-in GPS omni directional antenna 3. LED to show GPS signal fix or searching 4. Built-in super capacitor to reserve system data for rapid satellite acquisition 5. SDIO interface. 6. Operating platform: Pocket PC 2002/2003, Win CE, W