Supercap SBS is MBTechnology's most economical system consisting of a lightweight cap membrane supercap SBS and 2 or more layers of layflat SBS modified base sheet/interply. Supercap SBS is modified with SBS, a synthetic rubber. SBS modified membranes exhibit high multidirectional strength, excellent cold temperature flexibility, elongation and recall properties far superior to traditional asphalt roofing membranes. These outstanding properties provide supercap SBS with unusual resistance to "thermal shock" a major contributor to roof failure.