This is a brand new still in the wrapper, though torn open, Czech made tank checker.  This pressure checker was the product of a Czech firm called Sportklimex Praha, later called Aquacentrum praha.  This checker dates from about 1971 and is made of chrome plated brass.  It was made in Prague (Praha) and has a yoke very reminiscent of a Healthways regulator yoke.  It is very well built and attractive.    Any information about this item is welcomed from our Czech friends.