Self-adjusting tensioner, Arm Rotation 45 Degrees , For Chain Number Not Applicable, For V-Belt Size B, Pulley Outside Diameter 5 3/64 in, Maximum Tension Force 30 lbf, Arm Material Aluminum, Features Alloy Steel Compression Springs, Self-Adjusting Tensioner Eliminates Need for Regular Manual Retensioning, Minimum Tension Force 0 lbf, Mount Hole Diameter 13/32 in, Product Type Rotary Tensioner & Idler Pulley Assembly