Permobil Corpus ergo air. ROHO and Permobil have joined together to evolve Permobil's Corpus 3G positioning cushion to feature an optional ROHO insert for added comfort, support, and skin protection. The cushion combines the shape matching ability of the ROHO Dry Floatation® technology with Permobil's ergonomic design. The improved cushion design enhances the already revolutionary Corpus 3G seating system, providing you with the superior skin protection that ROHO is known for. This new cushion allows for improved pelvic alignment and stability while maintaining optimal support of both the ischial tuberosities and greater trochanters.