$69 Plus shipping and taxes.
This high performance solar charge controller increases battery life by preventing overcharging. Starts charging at 2.5 battery volts.Unique no battery drain - Battery standby power consumption is zero! In the dark they use absolutely zero power, ideal for PV systems where efficiency is important. Boaters can leave it connected all winter without draining the batteries. Other controls, which have a standby current draw, will drain the battery over the winter with no solar input, reducing the freeze protection of the battery.