To avoid the damaging of a battery contact piece with a removal jig at removal of a battery.

A positive side contact piece 36 and a negative side contact piece 35 are provided at a strobe base plate 30. The negative side contact piece 35 is fitted under the base plate 30 in a short protrusion, and the positive side contact piece 36 is set in bending at the tip of an extended part so as to oppose the the negative side contact piece 35. In order to remove the battery 33, one wants to push out a part of nearer to the positive side contact piece partly covered with the extended part 37, so as to push out the battery in the parallel direction. For that, the extended part 37a is provided with a notch 37c, through which an extruding jig 60 is inserted to push out the battery. Furthermore, in order not to damage the extended part 37, a retention member 61 magnetically attracting the battery 33 pushed out is structured so as to move separately from the extruding jig.