is has a diameter to fit a long bolt 22 but is elongated to allow the vertical placement of the arm 16 on the bolt 22 to be adjustable a plurality of teeth 112 surround the bolt hole 110 projecting outward from the first side 104 returning briefly to fig1 and 2 a bent arm 14 also fits in the gap 68 between the rings 48 50 of the body 12 fig5 and 6 show the bent arm 14 in more detail the bent arm 14 is comprised of a bent shaft 122 a ring 120 and a plate 124 the shaft 122 is an elongated member which is bent at a right angle near its center the shaft 122 has a first side 126 on the inside of the bend a second side 128 is on the outside and anterior 130 and posterior 132 sides one end of the bent shaft 122 connects to a ring 120 and the opposite end terminates in a plate 124 the ring 120 also has an anterior side 130 which is a continuation of the anterior side of the shaft 122 and a posterior side 132 which is a continuation of the posterior side of the shaft 122 in the center of the ring 120 is a circular bore 138 whose diameter is.