The FossForward Innovations’ LLG-5 Engine Heater Tester is a two-in-one tool that tests both the engine heater and its power source extension cord. A specific amp reading removes the guesswork from deciding when to replace an engine block heater. Easy to use, the LLG-5 can significantly reduce the number of needed service calls due to cold weather starting problems. Works well for regular PMs in the shop, and portable enough for vehicle site testing.