Fits GX160 & GX200.
The stock side cover and head bolts are grade 5 and will stretch causing flex and misalignment between parts. The grade 10.9 bolts and studs are much stronger. This kit includes studs for the cylinder head and bolts for the side cover. We use bolts on the side cover because the studs will interfere with the chain guard and chain. Highly recommended for big horsepower and high rpm applications.