which may be comprised of angle iron that is situated to provide a complementary shape to the cross section of the joist hoist beam 46 not shown in fig4 a thus the bracket 66 is provided with bearing surfaces 70 for sliding movement along the length of joist hoist beam 46 a gripper assembly pinch bolt 72 is provided on the bracket 66 in order to lock the position of the gripper assemblies 50 on the joist hoist beam 46 fig4 b further illustrates the dimensions of bracket 66 in a preferred embodiment of the invention it will be recognized that on each bracket 66 there is provided two gripping members 60 that are actuatable in opposite directions therefore the actuating rods 54 move in opposite directions with respect to the joist hoist beam 46 in moving the grippers 60 from the coupled to the uncoupled positions it is to be appreciated that in order to couple the gripping assembly to a joist section the crane is used to lower the assembly into close proximity to the joist section a worker then manipulates the hanging weight to move the actuating rod 54 to rotate the grippers 60 to an uncoupled position the device is then further lowered so that the hooks of the grippers are aligned with the.