You'll be fine with the toad fobs, just use a spoon to prise in the gap near the ring/slot at bottom right corner if facing you, then the inner bit board and battery just pops out in a silicone moulding, take out board, use a small pointed bit to prise/slide battery out, reverse procedure.
It would be pretty hard to accidentally break a toad one, I've never broke one in over 10 years.
tabetha