One Used Serdi  2003 three angle carbide tip holder for use in popular seat and guide machine wide body toolholders or Serdi or Newen 5300 series toolholders. part is OE Serdi.  Check my other listing. $12.50 to properly pack and ship to the lower 48 states. I always combine shipping. Thanks for looking. Don Dennis  For  valve seats
1.575 to 2.362 inches