PITTSBURGH, Nov. 25, 2025 /PRNewswire/ -- "I thought there should be a way to create a flush pavement surface over recessed manhole covers on roadways," said an inventor, from Mount Royal, QC, Canada, ...
PITTSBURGH, Feb. 21, 2019 /PRNewswire/ -- "I noticed a lot of sunken manhole covers while I was driving and thought there should be a simple way to level them," said an inventor, from Hershey, Pa., ...
PITTSBURGH, Jan. 10, 2019 /PRNewswire/ -- "I witnessed explosions and saw that manhole covers blow off, which is a real danger," said an inventor from St. Paul, Minn. "To keep manhole covers securely ...
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