GPSlim240: Holux GPSlim 240 Bluetooth GPS Receiver (SiRF III) The compact size and practical design of the GPSlim240 makes it both easy to carryand also wearable across the chest , making the style-conscious user look even more stylish. Use SiRF StarIII chipset. 20-channel GPS Receiver for fast acquisition and reacguisition. 200,000 effective correlators for fast Time To First Fix(TTFF), even at poor satellite signal. Built-in rechargeable Lithium-ion battery for at least 8 hours operation.