I’ve read it in some nofap related site that snapbands are great little devices for reebooting and that a lot of fapstronauts using it. I’ve never heard this, but i currently started to use them.
The point is very simple: wear a snap band on your wrist (not too tight, so it won’t sabotage your everyday activities), and whenever you zoning out while thinking about porn or masturbation, you pull the snapband and the little twitching pain will “snap you out of it” back to the current moment. Obviously the point is not self-hurt, inflicting pain on yourself or punish yourself, but to be aware of these triggers and take this action to prevent them to move forward into relapse.
I can testify, that personally for me it works! It’s not only a simple little practicality, but the snapband also reminds me of the commitment I’ve made everytime i look down on my wrist.