Specifications: Diameter (lawn trimmer accessory): 9.4cm Thickness (lawn trimmer accessory): 5cm Length (replacement blade): 10.5cm Thickness (replacement blade): 0.4cm Color: Black Weight: 383g Package Includes: 1 x Lawn trimmer accessory with 3 blades 20 x Nylon replacement blades Product Description & Details: 1. Our lawn trimmer accessory comes originally with three high-quality thick nylon blades that are wear-resistant and durable. Since blades are consumable items, we also provide 20 additional replacement blades for your convenience. 2. Our lawn mower accessory has a diameter of 9.4 cm and a thickness of 5 cm. The replacement blade length is 10.5 cm. The mounting hole diameter is 1.2 cm with a thickness of 0.4 cm. Our nylon replacement blades are securely attached with screws and are not prone to falling off during use, helping improve work efficiency and offering you great comfort. 3. Our replacement blades feature a smooth surface and excellent craftsmanship. Handle the blade with care to avoid cuts from the sharp edge. (Note: The blade is a small accessory. Keep it out of reach of children to prevent ingestion or injury.) 4. This nylon trimmer blade is compatible with Stihl ST 20-3 and is easy to replace. Simply remove the screw on the lawn mower and install a new blade. Note: 1. The blade is a small accessory. Keep it out of reach of children to prevent ingestion or injury.