This is a very energy-efficient bulb, perfect if you're trying to keep energy costs down. The socket on the bulb is the quite common E27 socket, also referred to as an intermediate socket.
Conrad Electronic
OSRAM 4058075607347 LED (monochrome) EEC E (A - G) E-27 Battery shape 7.3 W = 60 W Warm white (Ø x L) 32 mm x 90 mm 1 pc(s)