Made of strong PVC, velcro, steel 'D', polyester webbing. It is shaped for part of the arm to fold back to save the length for better storage. Ideal for carrying in a van etc. Two webbing straps to carrying it. The flap is to hold it in and fastened closed with 50mm velcro. A 'D' near the flap is if you want to hang it up to keep it safe and out of the way.