I'm planning on installing a 12 port double gang faceplate with about 10 cat5 shielded jacks. the customer wants the ability to put a cover with a lock on top of the faceplate. I am thinking of a small metal lockbox (that they use for security systems)

can any point me in the right direction for such a metal box, it only needs to be a little larger than a double gang faceplate with a lock.

i plan on mounting it over the faceplate, cutting out the back and putting a hole in the bottom for the patch cords to route.

If a need for security and lock box where are the patch cords going?
And just a thought why not use a 12 port patch panel in side the box thats a lot less cutting.

You can use a 12 port patch panel, or a double gang plate... and if you want to put a lock box -- you have a few options. The alarm ones (at least that I've seen) are fairly large, in the 12"x12" department, maybe some slightly smaller -- but all far too large for a double gang box.

I think your best bet would be to modify a key storage box that property management/hotels/real estate agents use. They make smaller ones that are about perfect size, MMF industries makes several varities, one I believe is 7x7x2.5" which would be PERFECT. You could put a grommet at the bottom for patch cords to exit, and cut out the back but leave a 1" or so edge to attach your screws to.

Their key boxes look like this: https://www.mmfind.com/keycontr.htm

Might try that... I can't think of a comercially available product that does that, although I'm sure there is somewhere.

thanks for the advice. this is what I found https://www.mierproducts.com/Default.htm

basically it's a restaurant, and the manager does not want the staff to mess with the Point of Sale patch cords. I offered a box, which he liked. too bad there is not something already manufactured for this purpose: to lock the box and keep out un-authorized hands. (hmmmm...$$$)

thanks!