New bike came with TPU tubes fitted so that's what I'm using and carry a couple of spares.
Question is about patching. The spares came with instant patches so in event of a puncture then possibility of sticking patch on.
However, unlike butyl tubes when if you get a puncture you can pump tubes up a reasonable amount to find a pin prick hole, with TPU tubes the advice is only minimally inflate when not installed in a wheel/tyre as otherwise they deform permanently.
So, how does one find a puncture on the roadside? At home be able to dunk in a bowl of water etc but oddly I don't carry one when out riding.
Hopefully this is a scenario I'll never need but always good to know.