For decades Star's service-type autos largely riffed off of Colt's Browning designs. In the 1970s they came up with an in-house, clean sheet of paper design that was eventually produced as the Model 28. (It has a lot in common with the CZ-75, but was designed at the same time, half a continent away. Both design teams were cribbing the same ideas, though.)
The Model 28 featured a double-action trigger, hammer-dropping safeties, a fixed lug with an enclosed cam path for unlocking rather than a swinging link, inside frame rails, and a captive recoil spring. The new pistol formed the basis for subsequent Star designs, of which the Ultra Star was the final evolution; the Ultimate Star, if you will.
The Ultra Star ported the basic formula of the duty-size Model 28/30/31 pistols over into a compact, single-stack form factor with a capacity of 9+1 rounds of 9mm. The big changes were the replacement of the Colt/Browning-type locking lugs on the barrel with a SIG Sauer-style shoulder over the chamber that locked into the ejection port and, obviously, the polymer frame. This would be the first polymer pistol from Star...and the last.
The manufacturer closed its doors for good in 1997.
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