spring 108 forces the piston 92 to the up or extended position and the piston is pushed down against the spring force j slots 110 on the piston 92 cooperate with the projections 112 on the cylinder to lock the piston in the down position therefore the piston is turned to lock and unlock the piston such as by the use of a coin 114 in the slot 116 another variation of the invention is shown in fig1 and 11 generally shown is a cylinder 118 attached to the carcass 120 of the ball and a cap 122 on the cylinder the actual layers of the carcass are not shown in this fig1 inside of the cylinder is a piston 124 with an o ring seal 126 and a piston rod 128 on the bottom of the cylinder is a one way valve 130 of the duckbill type in this embodiment the spring 132 forces the piston 124 and the piston rod 128 down into the cylinder so that the piston rod 128 is pulled up against the spring force and the spring forces the piston and piston rod down into the cylinder attached to the upper end of the piston rod is a flip up.