Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Resonably priced Battery charging system monitor

I purchased two Equus 3721 Battery and Charging System Monitor for my 1984 VW Vanagon Westfalia Camper that has dual batteries. I wanted to beable to monitor both batteries and make sure that the engine starting battery remains charged at all times to start the motor. The second battery runs all the internal camper electrics and I wanted to beable monitor its condition at all times. This unit does the trick just fine.