POLYPIPE PolyFit is the one step, fully demountable and re-usable push-fit plumbing system, which combined with Polypipe White Polybutylene pipe, creates a truly flexible, yet highly secure, plumbing system that is demountable and reusable when required. Barrier pipe: - Designed for central heating systems. - Incorporates an oxygen barrier to inhibit oxygen permeation. - Use of inhibitors is recommended as corrosion can occur in all types of system regardless of pipe material. - Can also be used for domestic hot and cold water services.