Eagle I is the MILD-HYBRID kit developed specifically for the conversion of inboard endothermic engines with shaftline. The kit consists of a Lithium battery pack that powers a Thor electric inboard, placed by the side of the endothermic engine and connected to the propeller shaft via a belt or chain drive. The system is supplied complete with battery charger and electric motor control devices however, throttle and display, can be installed separately in the dashboard or be integrated into the standard instrumentation in order to achieve an automatic and user-friendly system. The Thor inboard acts as the sole propulsion unit at low RPM and mutes into a generator that recharges the battery while the endothermic inboard is in use.