This listing is for two replacement slip clutch disc, 140mm OD (5.50") X 85mm ID (3-5/16"). Fits many slip clutch PTO shafts and Independent Slip Clutches. If your slip clutch will no longer take an adjustment, if your springs are bottomed out and your clutch still slips, if your friction disc are these dimensions and are broken or excessively worn they will need to be replaced. Most slip clutches will take 2 or 4 slip clutch disc depending on the model and torque rating of the clutch. Please check the dimensions of our clutch where the disc sits to make sure your dimensions match. Just change the quantity in the quantity to match the number of disc you need