Ridgid Manual Threading Pipe threader Die Set 1 1/4"  12-R NPT Alloy 37840 Dies, 12R 1-1/4 Npt This item is used for Handtools & Tool Organizers ,Other Hand Tools This product manufacture by United States 1 1/4" Nominal Pipe Size 11 1/2 Threads Per Inch (NPT) National Pipe Taper Used for OO-R, 111-R, 12-R, O-R, 11-R Ratchet threaders Also used for 30A, 31A 3-way pipe threaders