The Time-Teaser is a time-stopping device invented by Gyro Gearloose.
A successor to the broken Stopwatch, the Time-Teaser, created by Gyro Gearloose in 1987, is a time-stopping device resembling an ornate, but otherwise innocuous, stopwatch. When switched on, it speeds time up for the user sufficiently as to make it appear time has frozen for all but them. In this way, it is superior to the originally Stopwatch, as physical objects can freely be manipulated while in "frozen" time.
Shortly after its completion, the Time-Teaser, which Gyro intended to publicize through his "Invention of the Month Club", was filched by Huey, Dewey and Louie Duck, who used it to complete various tasks in a few minutes. After flirting with illegality in helping an unsuccessful baseball team win a match, they used the Time-Teaser for a noble purpose, namely foiling a group of Beagle Boys' attempted robbery.
However, this made the Beagles aware of the device; three of their numbers, Bankjob, Bebop and Babyface, stole the device and successfully used it to steal the contents of Scrooge McDuck's Money Bin. They were too rash in their attempt to escape aboard a steamer, though, and ended up shattering the Time-Teaser irreparably — although it went out with a temporal bang, enveloping the whole ship (fortune and Beagles and all) in a blast of time energy that hurled them two hundred years into the past, from which they were later rescued by Scrooge McDuck and friends aboard the Time Tub.
About thirty years later, in the parallel universe known as the 2017 Continuum, the local version of Gyro created his own Time-Teaser for McDuck Enterprises, only for it to fall into the hands of Flintheart Glomgold, who nearly drove Scrooge McDuck to madness and ruin by using it to mess with him (such as taking small amounts of money from his Bin). After Scrooge faked his death, however, Glomgold was tricked into revealing his plan. The Time-Teaser was briefly reactivated during the ensuing scuffle between the two billionaires; they briefly engaged it in reverse mode, freezing only themselves but leaving the rest of the world intact — a state from which Bentina Beakley eventually pulled them, confiscating the Time-Teaser in the process.
Behind the scenes
The Time-Teaser was the main macguffin of the 1987 story Time Teasers, and also central to the DuckTales 2017 episode The 87 Cents Solution. It predates its less advanced chronological predecessor, the Stopwatch.