Abstract: An adjusting device for adjusting the height of a net pole and the tension of a net rope so as to set up a net used, for example, for a volley ball game, comprises an outer tube, an inner tube telescopically inserted in the outer tube, a stretching means for stretching or releasing a net rope, and a drive means for actuating the inner tube to rise or fall along the outer tube and the stretching means. The drive means is completely housed in the outer tube and actuated by a detachable handle through an opening formed in the outer tube. The rope stretching means is provided at the top end of the inner tube and actuated by the drive means so as to stretch or release the net rope. The drive means is a counter-rotation preventing mechanism per se.

Abstract: An arrangement for fastening an upstanding post in a floorboard for use in indoor sports comprises a hollow cylindrical support into which the post loosely fits, having an opening provided in the circumferential wall thereof, the cylindrical support being embedded below the floorboard, a guide box which covers the opening in the cylindrical support, a headed screw rod rotatably supported in a vertical fashion in the guide box, a first wedge member screw-threadedly receiving the screw rod so that it may move upwards or downwards, a second wedge member received in the opening of the guide box so that it may move in the radial direction of the cylindrical support in accordance with the movement of the first wedge, a hole provided through the floorboard aligned in a vertical plane with the screw rod.