... strength of 18 lbs and a 3-strands core. Item: New Premier Pink Twisted Polypropylene Mason's String Line Material:PolypropyleneSize ... out sites, concrete and landscape layout, as well as brick/block laying. Shape is set and stabilized with a post-winding ... construction, ideal for staking out construction sites for concrete, brick, block or landscaping layouts. Keep It Handy When You Need It ...