Irwin 9434 Hanson 3/8"-16 NC Thread 1" Hexagon Machine Screw Die (HCS) - 1" across flats. Ideal for maintenance and repair work. Recommended for use with hexagon die stock. Die can be used with a wrench or socket when space is limited. Advanced die geometry: Allows for faster cutting with longer life. Material types: High carbon steel (HCS) for cutting of external threads by hand. Etched: Die size is etched on each tool for easy identification.