small Chubb dual control lock

I like collecting dual control locks, especially the ones where two keys operate through a single keyhole. Most of the ones I come across are quite large locks, but had to open this one recently for a bank that was closing down and wanted some old safes opened to check they were empty before disposal. This was on a Chubb record protection cabinet and I have not seen this lock before in dual control guise. I had to drill it as I didn't have any picks to fit, but managed to get it open without too much damage to anything except the lock cap, nice little lock design.

thats a nice lock Gary, it also looks a brass drill pin which is pretty unusual, I think the only brass one I have is on a Parsons Patent balance Lever made by Duce. you sure get your hands on some interesting stuff!

I certainly seem to see more dual control stuff due to doing a lot of bank work, but this was the first time I had come across this lock.
I also got a nice Milners locking escutcheon recently, which was another way the banks made single keyholes into dual control. Once I have made a pick for It and got it opened, I will put pictures up.