Actually I don't see how it would work on my key is has a outer nub. It's the Kyrpolok series. I'm not to worried I mostly ride in the KCK-KCMO areas most thieves around here wouldn't be smart enough to figure it out.
actually they all have that outer nub but it does not have an associated pin with it...
before i knew about this i had found my locks with the inner part turned halfway where someone had tried
the pen trick on it but broke the pen. I filed my outer-nub off to get the key to go in so that I could
unlock it and it works just the same. the inner nub does not have a pin either but it is there to actually
grab the center to turn it.
my locks are about 10 and 15 years old... im pretty sure if a pen fits in there it will do it..... it was not
easy the first go-round, but its painfully easy once you get to tapped back in there.
i think if there was a way to stiffen the turning part.... it would make it much more difficult.