A non-hormonal, reversible and non-toxic male birth control could be a step closer, with scientists successfully targeting a protein that's crucial in making fertile sperm. Knocking this protein out for a period of time would give men control over their protection window, much like oral…
Condom. You can see that it’s there. Closest you can get.
It is pretty easy to tamper with a condom in invisible ways, from poking holes or letting it expire, to stealthing. Hell, you can even cook the condom at low heat for a while in its package and you will cause significant structural damage to it, without even bruising most packaging.
Even a freshly bought condom and a little sleight of hand can go a long way into tampering. No birth control is trust free.