New Block heater kit Allis Chalmers 3500 / 3700 (670T, 670I 426CID) 10000 / 11000 (685T, 685I 516CID) 17000 / 21000 / 25000 (6138LT, 844CID) 1500 Watts, 120 Volt. 1" NPT Includes power cord, gasket, instructions Keeps diesel engine warm in cold temperatures. Eliminates cold start engine damage. Simple to install. Reliable and efficient way to pre-heat your engine.