Abstract: A lighting socket assembly (16) is mounted on an upper end of an L-shaped slide tube (A), such as a brass tube. A one piece, plastic clutch block (30) defines a cylindrical bearing surface (32) integrally therewith. The L-shaped tube lower portion (10) is slidably and rotatably received in frictional engagement with the cylindrical bearing surface such that the tube is slidable and rotatable therein. A threaded member (40) is threadly received in a bore (38) in the clutch block. A smooth inner surface (48) of the threaded member selectively engages the received L-shaped tube to adjust the degree of frictional engagement between the clutch block and the tube. By selectively advancing and retreating the threaded element with a manually graspable portion (46) rotational and vertical adjustment of the lamp assembly relative to the clutch block is facilitated. The clutch block is supported on a vertical rod or tube (60) which is mounted to a base (62).