AP Products 024-1001 Propane Tank Gas Level Indicator<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Includes One Magnetic Sensor</li><li>Mounts to bottom of LP tank</li><li>Communicates via bluetooth</li><li>Updates every five seconds</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41JbNaZcn6L.jpg" noproxy><img src="http://ecx.images-amazon.com/images/I/31mT6ASR6TL.jpg" noproxy>