The Harco "Knock-On" repair coupling’s unique gasket design allows for travel in both directions, making it as easy to slide the coupling back onto the existing pipe as it was to slide it onto the repair section.
The square face bell design allows for a larger object, such as a bar or wood block, to be placed against the fitting in order to knock the repair coupling into place. All Harco repair couplings are pressure rated to 200 p.s.i. and, with no bolts, nothing to tighten to engage the gasket, no glue and no set time before backfilling can begin, the repair coupling is completed as soon as it is installed. You can immediately turn the water pressure back on and resume normal operations.
The combination of all these features makes the Harco "Knock-On" repair coupling a simple and quick repair coupling. When the water is turned off time is of the utmost importance, so use Harco repair couplings and get your system running again immediately.