An apparatus (1) for changing a power source of a drone, the apparatus (1) comprises an adaptor (2) for securing a power source (3) to a drone and comprising a first energy connection for supplying energy from the power source (3) and a second energy connection for supplying energy to a drone, wherein one of the first and second energy connections comprises a pair of energy links (20, 21) which are movable between a first position (FIG. 5) to facilitate energy supply and secure the power source (3) to the drone and a second position (FIG. 4) to interrupt energy supply and enable the power source (3) to be removed from the drone.