21BH508 up for sale is a new electric fan motor acme #85 110 volt , see photos for model , also see photos for ID  , nice fan motor for many uses , the shaft has a outer diameter of 0.187 x about 1 inch long and the back has two mounting posts that are threaded for mounting it , these are about 2 inches apart , the fan has 5 blades and has a OD of 5 3/8 ,  the 110 volts runs into two wires at the top and on each side of the drive coil , see our store we are addding more items weekly , thank you for supporting a USA business we appreciate this , Rwk