NPT Carbon Steel Taps 1st 2nd Set NPT carbon steel taps available individually or as a 1st and 2nd tap set. These pipe thread taps are suitable for National Pipe Taper threads and are mainly used for cleaning, chasing and repairing existing internal NPT threads. Choose from NPT pipe... £11.44 (Inc. VAT) £9.53 (Ex. VAT) Choose Options Compare