PURPOSE: To fix a frame composed of angle members and channel members to a fixed member without protruding fitted pieces or the head of bolts in the specified fastening direction.

CONSTITUTION: A fixed member is nipped by one side 1a of a frame and one side 10a of a metal fixture by use of the metal fixture 10 having two sides 10a, 10b which cross each other with a larger angle than the crossed angle of two sides 1a, 1c constituting the frame. A bolt 8a is inserted in the frame 1c and the other side 10b of the metal fixture 10 and fastened to actuate the compression against the fixed member in accordance with the fastening force.