Drive Tensioner, Arm Length to Hole Center 1.375 in, Includes Tightener Shaft No, Mount Base Length 1 13/16 in, Mount Hole Diameter 1/4 in, Overall Length 5.5 in, Shaft Diameter 0.5 in, Shaft Length Not Applicable, Shaft Thread Size 3/8 In.-16, Thread Length 7/16 in, Compatible Tightener Shaft Manufacturer Part Number SO1, Mount Hole Center-to-Center Length 4 3/4 in, Number of Mount Holes 2