XS Scuba HP Two Port Adapter. 

Features:

• Add an additional high pressure port to your regulator’s first stage 
• Additional port allows for 360º swivel
• One 7/16”-20 male to two 7/16”-20 female outlets (common HP port)
• Chromed brass construction
• High pressure use - Maximum 5000 psi
• Cleaned for use with up to 40% pre-blended nitrox