Durable HDPE Tree Root Barriers , since 1989. Four widths available , 30cm,45cm, 60cm and 90cm , cut to size from 10 metre lengths. The right product to protect all hardscapes. Also available for above ground Advance Tree growers. An adjustable product to grow a tree from 150mm to 600mm in the one container and be able to root prune at any stage of growth. Affordable and reusable a proven system.