PURPOSE: To increase the speed for connecting two members to be connected and adjust the distance between the two easily by providing male threads and annular grooves in the same axis as the male threads and extending circumferentially on the outer periphery of the screw member.

CONSTITUTION: Male threads 7 of a screw member 5 is connected to female threads 4 of an insert 3 embedded in an interior wall panel 2. When the screw member 5 is pushed through a hole 14 in a fixture 9 into a recess 15 against a concrete bed 1 together with the interior panel 2, fixing pieces 11 and 12 deform elastically and their center ends 11b and 12b come over a crest of grooves 8 to make locking. Thus, the screw member 5 and the fixture 9, i.e., the concrete bed wall 1 and the interior wall panel 2 are bound together with each other. When a ring portion 6 is turned to turn the screw member 5 after the connection is completed, the fixing pieces 11 and 12 are turned along the annular grooves 8 and, therefore, the screw member 5 will not move in the axial direction of the fixture 9. On the other hand, the female threads 4 and the screw member 5 move in the axial direction relatively to each other to adjust the distance between both members to be connected 1 and 2.