Free-machining steel is steel that forms small chips when machined. This increases the material's machinability by breaking the chips into small pieces, thus avoiding entanglement in the machinery. This enables automatic equipment to run without human interaction. Free-machining steel with lead also allows for higher machining rates. Free-machining steel costs 15 to 20% more than standard steel, but increased machining speeds, larger cuts, and longer tool life offset the higher cost.