XS Scuba 1/4" NPT Female to 3/8"-24 UNF Male Adapter.

Features: 

• Converting your regulator / hoses to ¼” NPT has many practical application in diving as well as your garage or shop
• Used with surface supplied umbilicals, switch blocks, comm gear and pneumatic tools
• Viton o-rings where applicable
• Models made of brass are for low pressure only - below 200 psi