28 of the second plate 22 a circular opening 40 is contained on that portion of the pivot pin bracket 38 which extends beyond the plane side 28 of the second plate 22 the first end of a vertical pin 42 having a first end and a second end is fixedly attached to the front side 24 of the first plate 20 adjacent to the first plate 39 s 20 second end 34 the second end of the pin 42 is inserted into the circular opening 40 of the pivot bin bracket 38 a cap is attached to the second end of the pin 42 so as to maintain the rotatable connection between the pivot pin bracket 38 and the pin 42 in an alternative embodiment of the present invention a screw not shown can be used in place of the vertical pin 42 the screw would be rotatably maintained within the circular opening 40 of the pivot bin bracket 38 and removably attached to the front side 24 of the first plate 20 adjacent to the vertical pin 42 on the first plate 20 is a first annular opening 44 and adjacent to the pivot pin bracket 38 on the second plate 22 is a second annular opening 46 the first end of a spring 48 is removably attached to the first annular opening 44 and the second end of the spring 48 is removably attached to the second annular opening 46 the spring 48 causes the first and second plates 20 22 to rotate about the pin 42 to a closed position wherein the plane sides 28 of the first and second plates 20 22 are temporarily joined when in.