Helical Free Running Thread InsertPrecision Helical Free Running Thread Inserts are available in multiple lentghs.Made of A2 (304) stainless steel. M39 Helical Threaded Inserts$0.01PriceSizeM39 X 4.0 X 58.5Quantity1 pcQuantity*Call us toll-free at 1-800-638-7421Notify When AvailableAvailable MaterialStainless Steel