Accessories; this years DEMA Show. Since it's inception in 1994,500 psi has been making some of the finest Scuba Equipment Care Products in the industry catering to both commercial and recreational divers throughout the world. Enjoy a Clear Dive; and take advantage of this years DEMA Specials. Brands: 500 psi Brand Mask Defog, Mask Scrub, Stink Guard, Wetsuit & BC Wash. Also a Wet & Dry Suit Slide, Silicone Pump, Scuba Gear, Sports Suits ...