This is a coolant rotating joints serie. Seals are in tungsten carbide; a pair  of spaced ball bearings  are protected by a slinger (labirinth). This slinger directs any eventual seal leakage away from the bearings and out the vent holes in the housing so it’s possible the vertical mounting. The internal fluid passage, straight and without any resistance, minimizes the pressure drop. The sealing is ensured by three springs set outside the flowing fluid.It’s also available a type with axial inlet port.