Crankshaft KeySmall Block ChevyBig Block ChevyStock ReplacementLong-StyleSold Individually JEGS 601018 Long-Style Crankshaft Key is a perfect replacement for a worn key. Having worn crankshaft keys can result in timing gear to dampener positioning being incorrect which can cause your timing to be off and inconsistent.Dimensions:Length: 1.375 in. Thickness: .187 in.Height, bottom to top: .395 in.Note: For Small Block Chevy engines with two Key crankshafts we recommend JEGS 555-601016