The HP twin adaptor allows you to use both an SPG and a transmitter from a single High-Pressure port. This is especially useful for 1st stages that only have a single HP port. The HP twin adaptor utilizes a standard 7/16" thread and is suitable for use on all manufacturers 1st stages. Use this to add an additional high pressure port to your regulator&';s first stage Chromed brass construction with Viton O-rings High pressure only - maximum 5000 psi Cleaned for use with up to 40% pre-blended Nitrox (1) 7/16"-20 male inlet to (2) 7/16"-20 female outlets