Dura-Bond's USA Made high performance cam bearings offer more than double the fatigue strength of conventional bearings, allowing them to withstand higher valve spring loads, and they maintain the excellent surface characteristics of Babbitt. The load surface on these is highly polished to a mirror like finish. Made at Dura-Bond's factory right here in Carson City, (just a few blocks down the road from 440 Source) their cam bearings are the most trusted and well known in the industry.