This is a high performance polyester based bituminous membrane for longer lasting performance for pitched roofs and can be used as an alternative to a rigid felt support tray. Dimensions Length: 16m Width: 330mm Description Specifically designed to give lasting protection where underslating dresses into external gutters. Can be used with any underslating materials including breather membranes. Suitable for use on any slate or tile finish and can be used in both cold or warm roof configurations. This product is also rot-proof so it will not deteriorate, even when exposed to wet conditions for long periods of time.