I installed the Wolverine Model 16 about 3 years age, spliced the wires into the block heater plug and am amazed at how smooth startups are and how quickly the heat blows inside. Both heaters together use 1200 watts so I use a regular outdoor timer from Home Depot set to start 3 hours before I start the engine. Unless I'm mistaken, at 10 cents per kilowatt hour my 3 hours usage daily costs me 36 cents.