DescriptionHusqvarna® 350 / 410 1991-2000 Husqvarna® Various 510-610cc 1983 to 2001 We choose to use the copper based C63000 nickel-aluminum bronze as a material to make our bronze valve guides because of its ideal characteristics for the application. The 5% nickel content provides superior resistance to wear, and the approximately 80 percent copper content delivers outstanding heat conductivity. KPMI® guide profiles are designed to have minimal effect on the airstream while maintaining critical cross sectional thickness in high temperature areas, which promotes high performance and endurance.QuantityPkg. of 1MaterialC630 BronzeTypeIntake / ExhaustOutside Dia.: (G)0.4750″ / Std.A0.430″B0.465″C0.970″D1.110″E0.510″F0.2350″