FYI for you mechanical head typesLooks like these puppies are on close out special:http://www.zdmak.com/wbstore/main.asp?ACTION=prod&TYPE=&CAT=&SUB=&prod=&Search=valve%20shim&PG=2&LowCt=8I checked Samstag Sales and they wanted $7 more. Assenmacher doesn't carry them anymore.