enclosures and the nesting supports provides support over a substantial peripheral portion of the deformable enclosures centrally disposed in the concave support surfaces 42 and 44 along axis of movement 20 are passageways 46 and 48 respectively each deformable enclosure includes a gas conduit for ingress and egress of gas in the preferred embodiment deformable enclosures 34 and 36 are provided with fittings which extend through passageways 46 and 48 with a length of conduit material being connected to the fittings for deformable enclosure 34 the gas conduit formed by the fitting and conduit material is designated 50 and for deformable enclosure 36 the gas conduit formed by the fitting and conduit material is designated 52 to control the ingress and egress of gas to deformable enclosures 34 and 36 a system of valves is provided on base 12 separate valve assemblies for actuators 14 and 16 are mounted on a support 55 on base 12 valve assembly 56 is associated with the plunger of actuator 14 and valve assembly 58 is associated with plunger 18 of actuator 16 fig3 provides a side view of valve assembly 58 and fig4 illustrates the various tubing connections required the tubing and valves shown in fig1 and 4 control the ingress and egress of pressurized gas to deformable enclosures 34 and 36 as noted above each deformable enclosure has a single gas conduit line for ingress and egress of gas conduit 50 for deformable enclosure 34 connects a pair of branch.