This bag is made with Nylon and the fabric is recognized for being flexible, but also valued for its durability and toughness. It supports a standard 20" x 20" box fan. Not only is this a great way to keep the fan secure to a place and prevent your horse from knocking it over, but this bag also allows you to have a fan blowing on your equine friends during those summer months to help keep them cool. When the horse is next to the fan or if fan is set up in the stall at an angle position up high, it will help reduce flies in the stall. This portable, space saving bag has adjustable straps with nickel plated bolt snap and rings. It will keep fan securely in place. *Fan not included