all i know about them is your kinda knackered if you dont have the key for them as they dont have a code on them 😞
i did look into this a while back as i have one with no key & all i could find out was there is a chap in san diego i think that can re-build them & provide a new key, but for the price he wanted to do it i could have bought another one complete with key.....ill try to dig out his email address if you want it ?