8 hole belt pulley that I came across in the corner of the shed.  It is missing that backing plate...as you can see in the pictures.  I believe it can be used on the Super H's, M's, WD6's, maybe the 300 or 350?  The cast part number is 358598R91.  You are responsible for determining fitment.  Please look at the pictures and ask any questions prior to purchase.  Thanks