Unidentified Remote Combination Viewer Vaults

[Huw Eastwood]

If you look closely there are two indentations on the glass door frame which leads me to believe a security bolt was also used there as well.

It's highly unlikely they're using those security fixing bolts tbh- those parts are going to be purpose made for that door.

Don't forget that 2-point configuration has been around in industry for donkeys years and it's still used on fixings today on bearing retainers, spindle locks, annular rings, guide sleeves etc.
In many applications it's actually the only way when parts are flush or recessed and flats or hexagons can't be applied.

In fact you should recognise the two holes and associated wrench if you've ever changed a grinding or cutting disc on an angle grinder- Its still the most common method of tightening the central nut.

The adaption to standard sized bolts and fixings available off the shelf as 'tamper resistant' is relatively recent in comparison, and any machined pin or similar part with 2 holes will of course look exactly the same when viewed from the end.

[Huw Eastwood]

Here's another side view where the alternated anti-drill dowels are just visible down the door edge- that's one thick door!

[Chubby]

What material would they use in anti drill dowels.