To prevent the falling of an L-shaped spanner from an L-shaped spanner holder formed in a tool housing.

The L-shaped spanner holder comprises a vertical hole 17 in which a head portion 15a of the L-shaped spanner 15 formed almost vertically on a wall face 6a of the tool housing 6 is inserted and a recessed groove 18 in which a tail portion 15b of the L-shaped spanner 15 formed along the wall face 6a is inserted. An escape face 20 for making only a rear end 15d of the tail portion 15b of the L-shaped spanner 15 contact the bottom face of the recessed groove 18 is formed on the bottom face of the recessed groove 18 ranging a position corresponding to a bent portion 15c of the L-shaped spanner 15 to a corresponding position close to the rear end 15d of the tail portion 15b.