The robbery happened around 5:00 p.m. Monday at Murphy Jewelers in Upper Saucon Township.
Surveillance video shows the thieves breaking into one of the display cases, swiping more than a quarter million dollars in Rolex Watches.
However, the losses could have been higher.
"I had special display cases designed that are shatterproof and bulletproof and they were able to penetrate the glass," said owner Patrick Murphy.
Investigators are now looking to see of these three men may have also been involved in several other smash-and-grabs across the region, including one at a jewelry store inside the King of Prussia Mall.
No one was injured by there are plenty of witnesses, since the robbery happened in broad daylight.
The owners of the store are offering $10,000 for information that leads to the conviction of the three thieves.