The Nitecore NTC2 tail switch is compatible with 21700 flashlights with a single tail switch. Momentary-on and constant-on can be accessed using the tail switch. The U shape design prevents accidental activation and can also be used as a tail stand.
The NTC2 fits the following models:
MH12S, MH25S, MH12 V2, MH25 V2, NEW P12, NEW P30.