I remember that regulator from 1975, definitely Sportsways.
A flow through balanced piston first stage that was trying to compete with Scubapro Mk-5. in some ways similar to the competition from the USD Calypso IV.
In Puerto Rico we had a newly open dive shop (in 1975) that offered that regulator as their flagship competition to our Scubapro regulators.
Buceador con escafandra autónoma clásica.