Total Blackout Fabric, perfect for media rooms and bedrooms where blackout is needed. This is much better solution than anything inside the house. Heavy Duty Zipper Track System. Manual Crank or Motorized operation. Custom made up to 18' wide x 12' tall. Able to withstand high winds & blocks wind in winter. Very Stable System. Extruded Aluminum Cassette is 5" x 5".