Sidewalks and residential parking. Included Outlet Connector and Adaptor fit 4" sewer and drain pipe. The grates on this system are fully hand-removable for easier cleaning, No screws or bolts.Interlocking connections for a fast and easy installation.
I used them in #57 rock with curved rebate at the 4 drain pipe & drilled 2 holes in bottom in each 3' section & put all thread dowel with 2 nuts & washer hammered about 12" deep to hold & ran about 4" of gravel underneath with 4" Ky pipe ( corrugated 4" drain pipe with holes on the bottom) on a pitch to make a double way for water to drain.