To position a terminal without using a fixing jig to be mounted to a battery holder, to mount and fix the battery holder in matching with it, and to easily remove and restore the battery holder.

An insertion channel opened toward a board 4 side, and fitting claw 14 fitted to the board 4, when a battery holder 1 is mounted are provide in the battery holder 1. Thermals 2, 3 are constituted of the first contacts 23, 33 contacting with a battery 50 elastically, crimps 21, 31 inserted from the board 4 side into the insertion hole to be fixed, and the second contacts 22, 32 pressed to lands 41, 42 which are provided in the board 4, when the battery holder is mounted.