What do these do exactly? I figure the skin would add a boost die to Medicine checks when used with a medkit, but not so sure about the flesh.

As far as I can tell, synthflesh is really only used to cover cybernetics. Synthskin at 10/"dose seems to allow a single use of the medicine skill, but it really isn't stated. At least that's how I am treating them.

No boot dice though, that's a function of the full medicine kit.

Quite a necro here, but yeah. I second the question.

What does synthskin do? Does it affect Medicine checks? Is it just narrative? It can't be required for Medicine checks because of the logistical difficulties involved, but I'm really pretty clueless on this. At least FaD clarified that it's a single use application.

Aid in disguise checks to fool facial recognition, hide smaller items "under your skin", aid in staunching bleeding and certain critical injuries (narratively, but also aesthetically, preventing/reducing scarring, filling holes of blown away sections of the arm...?)

In some instances I'd consider letting it grant an auto-success, in others an auto-advantage, in some cases a boost die (perhaps). Depending on what it's used for...

I just cross out 1 from the sheet, when it makes sense. Otherwise doesn't do anything. It's kinda roleplayish thing.

However, I'd definitely let my players use it creatively as described above.