The 28-cm3 (11-in3) Innas variable floating cup pump offers up to 95% part load efficiency at various operating points in full displacement at an 8° swash angle. At decreasing swash angles, efficiencies gradually decrease because the pump features no pressure-dependent contact forces between the pistons and the cups in which they run. The floating cup concept is an axial piston principle for hydrostatic pumps, motors, and transformers that permits through drive of multiple units. Featuring a low sound output, the concept prevents a source of friction that typically appears in conventional axial piston units, improving efficiency. Each piston has its own cup-like cylinder free floating on a barrel plate, and the floating cup principle can be made variable by changing the port plate angles on which the barrel plates are rotating.