What follows is my understanding of the V10-P threading possibilities based on Emco-Maier literature.
Assuming the machine in question is an English (inch) model, then there are 24 inch threads (and feeds) available directly (through lever change) at the Norton type quick-change gear box.
The inch machine can also cut precise metric threads via the Universal quadrant and change gear set which were optional.
There are 12 wheels in the set, seven of which are mounted, in various combinations, to a special "universal" quadrant to provide a range of metric pitches. Each of the six possible gear combinations will yield 5 to 8 pitches (available through the quick-change gear box levers) with some duplication. A total of 19 different metric pitches are possible altogether.
The Universal Quadrant and change gear set will be required to cut metric threads on the inch machine. The inch leadscrew will necessitate the half nuts to remain closed during threading operations.
The same applies to metric machine owners who want to cut inch threads, only the Universal Quadrant is different for the metric machine. The change gear set for either inch or metric is the same with 12 wheels of 25, 30, 35 and so on, to 80 teeth.
The Universal Quadrant and change gears are used in place of the Standard Quadrant. The Standard Metric Quadrant carries four gears arranged in one permanent combination. The Standard English Quadrant carries five gears in a single, permanent combination.