Two masked men used bolt cutters to gain entry to the substation at 444 Gravel Pike in Perkiomen, troopers said.
They then stole copper wiring from the loading dock, according to investigators.
Suspect one was 5-foot-11 and about 180 pounds with an average build, police said. He wore a gray hoodie with the hood cinched tightly around his face, black sweatpants, and gray sneakers.
Suspect two was 6-foot and about 200 pounds, also with an average build. He wore a black ski mask, a black hoodie, black sweatpants, and black sneakers.
Anyone with information is asked to call PSP Skippack at 610-584-1250 or submit a tip online.
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