directly attached to the piping system outlet 12 or via a support ring 24 the support cage 34 is typically made of circular cross section steel rod or bar but can be made from any suitable material or configuration in operation the support cage 34 provides the transition part 18 with ample support against inversion additionally the support cage 34 is manufactured to rest along the inside wall of the transition part 18 matching the contour of the duck bill shape of the transition part 18 when periods of high back pressure are encountered the transition part 18 rests against and is supported by the support cage 34 this support cage 34 is especially applicable in large particle or slurry applications in applications where very low pressure drop is required and the particle size of the fluid is small support plates 36 and 38 can be attached to the sides of the support cage 34 as seen in fig1 the support plates 36 and 38 provide higher surface area for the transition part 18 to rest against further the connections between support cage 34 and support plates 36 and 38 for example by welding effectively distribute the stresses in the transition part 18 during periods of back pressure and back flow in a fourth embodiment of the present invention the greatest protection against inversion is through the usage of a truncated cone support 39 as seen in fig1 this truncated cone support may be attached to a support ring 24 or attached directly to the end of the piping system outlet 12 the basic structure of the truncated cone support 39 is a hollow cone with the tip of the cone removed the shape matching the contour of.