ACDelco Belt Tensioner - 38511 Part #: 38511 Line: ACD ACDelco Belt Tensioner 1 Year Limited Warranty Material: Steel Pulley Outside Diameter (mm): 75mm Pulley Width (mm): 40mm Belt Type: Serpentine Pulley Width (in): 1-9/16 Inch Pulley Outside Diameter (in): 3 Inch Number Of Mounting Holes: 1 Pulley Inside Diameter (mm): 30mm Show More Show Less