- All valve guides are made of Ampco-45, a high-performance compound with 80% copper content to provide great heat conductivity and 5% nickel content for wear resistance
- Made in the U.S.A.
KTM -- 450 MXC -- (2004, 2001, 2006, 2002, 2005, 2000, 2007, 2003); KTM -- 450 SX Racing 4-Stroke -- (2007, 2001, 2006, 2004, 2005, 2000, 2003, 2002); KTM -- 450 XC-W -- (2001, 2006, 2007, 2005, 2003, 2000, 2002, 2004); KTM -- 540 DXC -- (2000, 2004, 2003, 2007, 2001, 2005, 2006, 2002); KTM -- 450 EXC -- (2000, 2005, 2007, 2001, 2002, 2006, 2003, 2004); KTM -- 450 XC -- (2005, 2001, 2003, 2007, 2004, 2002, 2006, 2000)