Wireless Multimeter Bluetooth Battery Monitor In Stock and shipping! Easy installation, free app on Google Play. Completely weatherproof and designed to be permanently connected to batteries in any environment. Extends battery life by allowing you to monitor power draw. Shunt is optional! An internal current sensor measures up to +/- 30 Amps. New for 2018! Datalog capability- store data every 24 hours or up to 1 second.