đ€ż Used Full-Face Diving Mask â For Sale Brand: OCEAN REEF â Neptune Space Type: Full-face diving mask with integrated regulator Condition: Excellent, gently used Features: â Built-in regulator â Wide field of view â Comfortable and secure fit â Great for professional and recreational diving NEPTUNE SPACE 50/60 PSI These full face masks have the intermediate pressure of the regulator set up at 50/60 PSI, allowing the use of the mask with an alternative surface air supply (hookah). Performance of the Neptune Space 50/60 regulator depends on the stability of the intermediate pressure provided by the surface air line supply.