Assortments by thread system
An assortment gathers hand taps and dies for a whole thread system in one case. 48 compositions are available, arranged by M and MF, tapered version, UNC and UNF, BSW and BSF and G (BSP) and NPT.
Choosing by size range
Within the metric series the span runs from the 64-piece set for small threads M 1 to M 10, through the common workshop sets M 3 to M 12 and M 5 to M 12, up to sets covering M 5 to M 30. For fine threads there are separate compositions, for example M 3 x 0.35 to M 12 x 1.5 or M 6 x 0.75 to M 24 x 1.5.
The tapered version
In the tapered sets such as the P.K.20 and the P.K.21, all three tools have the full outside diameter and differ only in chamfer length. Each can finish the thread on its own. That is practical when you would rather not work through the whole set every time.
Pipe threads
For G (BSP) there are sets from 1/8 to 1 inch with 26 or 32 pieces. Pipe threads are not a special case but a system of their own with a different flank angle; the differences are explained in Thread types explained.
Square dies
One set combines hand taps with square dies from M 3 to M 12. Those run in their own holders and have the advantage wherever more torque is needed.
Tap-only sets are under hand taps, die-only sets under round dies, sets for the machine under machine taps.
