Subcoil is specifically designed as a low cost rehabilitation system for distribution mains and small trunk mains. It uses a Polyethylene (PE) liner which is factory folded and held in a heart shape. This folding procedure creates a clearance allowing the fast installation of the liner pipe into the host pipe to be renovated. It is designed for thin wall application for pipes from 95 to 300mm diameter.

The folded liner pipe is inserted into the existing main and pressurized to snap the restraint allowing it to revert back to its original circular shape.