Gerald Michael Majchrzak, 66, was convicted of robbery, conspiracy, theft, and weapon possession following a two-day trial, said county authorities.
Middletown police said they received an "abandoned" 911 call from the Infinity Smoke Shop at 1236 E. Lincoln Highway just before midnight on May 5 last year.
When they arrived, employees told officers they were robbed by a man with white hair in a blue surgical mask, a blue zip-up hoodie, and sunglasses, authorities said. Footage from the shop's security system showed the suspect pointing a handgun in their faces, police said.
He made off with $3,000 in cash, two cartons of cigarettes, and a package of condoms, according to investigators.
Detectives later identified Majchrzak as the gunman and 46-year-old Timothy Allen Baker as his getaway driver.
Baker, of Bensalem, has pleaded guilty to conspiracy and is due to be sentenced in October, authorities added.
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