To use a simplified clamp, used for nipping a plurality of woods to adhere woods, for a member fixed on a wall surface and a ceiling surface.

Fastening arms 3 and 4 are slidably inserted in a square columnar main lever 1 and fixing bolt body 5 is arranged at the fastening arm 4 on the opposite to the fixed arm. A press bolt body 6 consisting of a thread shaft part 61 threadedly mounted on the fixing arm 2, a grasping part 62 rotationally operating the threaded shaft part 61, and a universal joint part 63 to intercouple the threaded shaft part 61 and the grasping part 62 is mounted on the fixed arm 2 arranged in a branching state on the one end side of the main lever 1.