Clevite H-Series performance bearings have a medium level of eccentricity, high crush, and a hardened steel back and thin overlay. These bearings are made without flash plating for better seating. Use H-Series bearings with crankshafts that have oversize fillets and where engines run in the medium to high RPM range. Manufactured from cast copperlead, increases fatigue strength by approximately 20 compared to powdered metal processes, referred to as sintering, which is used by the competition HSeries bearings are narrowed for greater crankshaft fillet clearance All HSeries bearings are made in Atlantic, Iowa USA High crush for better seating and retention Unplated hardened steel backing for better dimensional accuracy and bore contact