Easy installation with threaded mounting nuts. Recess diameter: 52 mm. External diameter: 57 mm. Mounting depth: 43 mm. Built-in LED light. Power consumption: 45-95 mA. Power consumption with light: 72-150 mA. 12 V only. NOTE! The tachograph can only be used in 4-stroke engines with 4 or 6 cylinders. It cannot be used in 2-stroke engines or engines with a different number of cylinders.