If the chain is forced into a U configuration with the master link at the top/bottom?
of the U then strong fingered types can push on the rollers squeezing them together
to pop the master link loose. I always have to use needle nose pliers to squeeze
the rollers together. The pin ends are held in a hole that looks like an "8" on its side.
Squeezing pushes the ends of the pins from the small part of the 8 to the large part,
allowing the plates to be pulled out of the chain. Once you have done it, it is easy.
Reassemble in reverse and just pulling moderately hard on the chain will pop the pins
back into the retention position (grab chain on either side of the master link with your
hands and pull. Works great, allows easy removal and they don't degrade with removal. Just dont lose the two pieces of the master link
. Steve