FeaturesUser adjustable shut down delay after engine shut off: 2, 15 or 30 minutes and 1, 2, 3, 4, 5, 8 12 hours.Rugged, water proof construction. Easily installed in engine compartments or high vibration environments.Super low standby current draw of 4 mAh will not drain your battery.Smart! No ignition wire is required.Overvoltage protection: Automatically shuts off at 16V with Auto reset.The voltage sensing APS-12 is an automatic switch designed for 12 volt vehicle electrical systems with negative ground. The model APS-12 timer is rated at 25 amps continuous duty. Using the 10 position rotary switch, you can select one of the following timer settings of: 2, 15 or 30 minutes and 1, 2, 3, 4, 5, 8 & 12 hours after the engine shuts off.The compact APS-12 should be installed in between the vehicle battery and the DC load. Typically, the load is a two-way mobile radio, mobile computer and other vehicle DC electronics. Standard installation involves installing the APS-12 in between the battery and the DC feed side of the radio using the supplied ring terminals. When installing the APS-12, you need to connect (positive and negative DC power IN & positive and negative DC power OUT). No ignition connection is required. This model can be installed inside of the vehicle or engine compartment as these units are waterproof.Over Voltage Protection is included in the APS-12 unit. Should the APS-12 timer ever receive a voltage of 16 volts or higher, the unit will automatically shut off protecting the electronics connected on the load side of your APS-12.SpecificationsAmperage Rating: 25 Amps max @ 12V continuous dutyLow Standby Current Draw: 4mA in standby mode, 100mA normal operation modeCompact Size: 3.5"L x 2"W x 1.5"HWeight: 0.5 lbs. (229 grams)