For Ryobi 301124004 P503 P505 P580 Circular Saw Depth Adjustment Knob Easy to install, saving time and money. Super durable. Please confirm that the model you need to buy matches our model before ordering. Made of durable high quality materials. Compact and sturdy, built to last. Quality Assurance: Well-designed, well-crafted. This is the manufacturer's replacement and is functionally equivalent to the previous part. After-sale guarantee: what we have been pursuing is customer satisfaction. If you are not satisfied with the product, please contact us! We will show you our sincere attitude and satisfactory solution