RIDGID 47750 Threading Machine Dies, Right-Handed Alloy NPT Pipe Dies with Nominal Pipe Size of 1-Inch to 2-Inches for Universal Die Heads Fits RIDGID NPT Universal Machine Die Head Nos. 504A, 711, 713, 811A, 815A, 816, 817 and 842 Alloy threading die material Threading dies have capacity of 1-inch to 2-inch Right-Hand, NPT (National {American} Pipe Tapered) thread RIDGID 47750 NPT dies have 11-1/2 TPI (Threads Per Inch)