Taper thread, British Standard Pipe Taper thread (BSPT), whose diameter increases or decreases along the length of the thread.
For producing precision threads by hand tapping, for starting threads - either second or bottoming taps should used after to achieve desire thread depth.
Taper pipe reamer recommended prior to tapping Rc (BSPT) thread forms
General purpose use
Threads per inch 14
Overall length 96mm
Cutting length 28mm
Drill diameter 23.75mm
Brand Somta