The number one goal of ATI performance is to supply highquality racing products. with a great team of innovative designers we are able to get better as a manufacturer and our ideas bring our products to a new level, finally makes the end user, the racers better at what they do.Features. Super Damper harmonic balancer shells are specifically designed for highrpm engines. Tuned to eliminate harmful crankshaft harmonics that cause parasitic horsepower loss. These damper shells are engineered to all but eliminate worn parts and timing problemsCompatibility. 1959 Chevy 3BSpecifications. Finish Black Zinc Chromate. Material Aluminum. Engine Balance Internal. Outside Diameter 7.074