Engine is a B16 1.6 liter car enginer with a speed regulator added to the timing gear and a Zenit carburetor. Early models had 4 speed gearbod, later models had a 5 speed gearbox. Bolinder Munktel Terrier 424 and Volvo 425 Krabat were identical except from Volvos being red while Bolinder Munktel werer green color with red engine and wheels.