Metric threads are the most commonly used type of general-purpose threads worldwide.
Each thread is characterized by its major diameter (D) and its pitch (P). ISO metric threads consist of a symmetric V-shaped thread. In the plane of the thread axis, the flanks of the V have an angle of 60° to each other.
Same as Metric but with finer pitch (P)
British Standard Pipe (BSP) technical standards for screw threads that has been adopted internationally for interconnecting and sealing pipes and fittings by mating
an external (male) thread with an internal (female) thread.
It has been adopted as standard in plumbing and pipe fitting, except in North America, where NPT and related threads are used. Symmetrical V-thread in which the angle between the flanks is 55° (measured in an axial plane)
American National Standard Pipe Thread standard, often NPT for short. U.S. national technical standard for screw threads used on threaded pipes and pipe fittings.
The taper rate for all NPT threads is 1 inch of diameter in 16 inches of length measured by the change of diameter over distance of thread. The angle between the taper and the center axis is 1.7899° or 1° 47′ 24″.
Unified National Coarse Thread, commonly used in the United States and Canada. It is the main standard for bolts, nuts, and a wide variety of other threaded fasteners used in these countries. It has the same 60° profile as the ISO metric screw thread, but the characteristic dimensions (outer diameter and pitch) were chosen as an inch fraction rather than a millimeter value. The UTS is currently controlled by ASME/ANSI in the United States.