“Residual pressure valve Adapter” has been added to your basket. View basket O2 Union 4mm Y, one-touch€ 6,00 One-Touch (Push-to-Connect), 4mm, Y union. In stock (can be backordered) O2 Union 4mm Y, one-touch quantity Add to basket Categories: Adapters & parts, Oxygen Description Description O2 Union 4x4x4mm Y, one-touch. Related products Out of stockOxygen/Oxygen cylindersMountain High oxygen cylinder Read more Oxygen/Adapters & partsO2 mounting bracket for MH AL-248/415/682 cylinders € 59,50 Add to basket Oxygen/Oxygen bagsO2 cylinder bag – black € 69,00 Add to basket