silvfox1200 wrote:That could have four pins and also as anti bump pin in the back. Not really sure. Mine has a 5UP on it and it appears to have anti-bump pin.which you could say has five pins but only four are actually used for the bitting. So if you are actually causing the last pin to rise into the Bible then that would cause it not to open. I have never had that problem but I guess it could happen.
For the first time, have seen one of those 5UP locks. Actually, received it with a number of Master padlocks that needed keys made, half of them were mine to keep afterwards. There was a 1UP, 3UP and a 5UP. Turns out the batch were keyed alike, so after impressioning four of them, just copied the keys for the rest. The 5UP did not have security pins, and was only four pins.
By chance, are the xUP series the ones you get where you put in the key and hammer it in to key the lock to your existing key?
Gordon
Just when you finally think you have learned it all, that is when you learn that you don't know anything yet.