The STIHL RAPID™ Duro 3 chain is a low-kickback version of the previous model. It stays sharp up to four times longer than standard chains. With standard-sized cutters, the RD3 is extremely durable and produces very good results in all types of wood. It is especially suited for cutting dirty wood, treated wood, roots, and hardwoods, which would quickly dull conventional chains. This chain must be re-sharpened with a formed diamond grinding wheel. Applications: The RD3 chain is especially suited for cutting dirty wood, treated wood, roots, and hardwoods. Unsure which type of saw chain you need? Download our Saw Chain Selection & Identification Chart for easy reference when replacing your STIHL saw chain.