YOU ARE BIDDING ON AN ST V51-56-60 ALLEN TYPE HEAD SCREW SET. ALSO HAVE SCREW SETS FOR MOST O.S ENGINES.INQUIRE. I  HAVE ALL TYPES OF OS & ENYA C/L VENTURIS & NVA FOR SALE OR ON AUCTION.IF YOU DONT SEE IT ASK.SEE MY OTHER AUCTIONS FOR PARTS.WILL COMBINE SHIPPING.  Check out my other items!Be sure to add me to your favorites list!