This is a power module from a working Viking MA339 36v lawnmower. These retail (if you can find one) for £90 so grab yourself a bargain.
VIKING MB545VR Petrol Lawnmower front axle 6340 700 2401 B38
Ignition Coil Module Stihl Viking 2 MB248T Lawnmower Petrol Tested
Einhell Cordless 36v Lawnmower 33cm Cut Brushless + Grass Trimmer 2x Batteries
Einhell Cordless 36v Lawnmower 33cm Cut Brushless + Grass Trimmer 3x Batteries
Spear & Jackson SCR3644A 44cm Cordless 36V Lawnmower No Battery Charger Used
Spear & Jackson SCR3644A 44cm Cordless 36V Lawnmower No Battery No Charger