M42 and M48: why diameter is not enough
Check diameter, pitch, gender, and the parts between them before ordering an adapter.
Read the whole thread specification
M42×0.75 and M42×1 have the same nominal diameter but different pitch. They are not an interchangeable pair. This tool requires the pitch explicitly, with male or female at the end, such as M42x0.75 female. The multiplication sign × and ordinary x are accepted.
Complementary genders, matching dimensions
Each outgoing interface is compared with the next component’s incoming interface. Matching metric diameter and pitch plus opposite genders produce a nominal match. Two male interfaces, two female interfaces, or differing dimensions require review.
Unknown means inspect, not incompatible
Bayonets, push-fit barrels, proprietary couplings, and incomplete labels are not resolved by the metric-thread parser. They remain unknown rather than becoming a false match. A valid nominal thread does not establish available engagement, shoulder contact, radial clearance, or sensor alignment.