ATLANTA -- Leading experts say the regular locks most of us have may actually offer a false sense of security.

"What you think is keeping you safe is mostly vulnerable," says security expert Marc Tobias.

Tobias says he’s popped thousands of ordinary locks. He used a technique called bumping. You insert a specially cut key, and give it a whack.

"It causes all the pin tumblers in the lock to split and the lock opens. And, it doesn't matter whether it's a deadbolt lock on a business or a lock on your house. Chances are, it can be rapidly bumped open," he said.

Locksmiths have been doing it for years to help homeowners. The International Association of Investigative Locksmiths say the worry now is that thieves can buy the specially cut keys online – along with instructions on how to bump.

"Someone that's looking for jewels, looking for collections, looking for high priced items would probably have the capability of doing it," said association spokesman Donald Shiles.

"It can be five seconds, it can be under a minute. But, at the end of the day, about 95-percent of them can be bumped open," said Tobias. He even bumped open a mailbox lock.

"It's pretty serious, especially when you consider that more than five million post office box locks can be bumped open in the same fashion, which is perfect for identity thieves," he said.

Tobias notified the U.S. Postal Service about the threat. The Postal Service says it, “Identified a number of potential vulnerabilities that might allow a person to gain unauthorized access. A number of security measures have been taken and postal employees have been asked to remain alert.”

High security locks can reduce the threat, but they run about $100 each.