These SITEWORX concrete and screed fibres are made from 20mm polypropylene and designed to minimise shrinkage and cracking in concrete and screed mixes. The SITEWORX range of building and DIY products provide professional building products and site consumables for trade and DIY users. These essential products provide what’s needed to ensure a site or building project operates to a high standard of workmanship, safety, tidiness and productivity.