SW-S, Standard OmniSwivel, Standard 9/16″-18 threaded 2nd stage regulator to standard low pressure scuba 9/16″-18 male.
Accepts in-line Quick Disconnect.
3way 360 degree rotation.
If it is your desire to have a much much higher quality and therefore priced unit this is the way to go. TSDS staff use both the less costly type and the Omni Swivel. The big difference is quality and cost; even at the staff cost some feel a Chevy runs down the road as well as a Rolls Royce (which is a good way of describing the less costly and a Omni Swivel) but the staff that justify the cost like the effortless smoothness of the Omni Swivel. It is worth the extra cost once you try one.
The Staff of TSDS have used swivels on their various 2nd stages of regs for years. It drastically reduces mouthpiece soreness and makes a Full Face Mask more comfortable also; no pull !!