The HPFF2 is an externally pressurized expansion compensator that has several advantages over other in-line bellows joints. Since the pressure is on the outside of the bellows, more corrugations can be added to the design resulting in a joint capable of more movement. The design features pipe that acts as a liner and a casing that acts as a cover to Protect the bellows from damage. An internal guide makes this a stable, rugged joint.