Bombsite Boxes Destroyed by Any Damage

Hey guys, long time no see. To make a long story short, since I'm
out of school for the summer I started mapping again. I'm still
working on the same project and it's getting towards completion.

Here's the problem. It's a de map and I made the bomb site
successfully, explosion works, everythings fine but one thing.
The boxes that are around the site are supposed to give cover to
Terrorists guarding the bomb but they can be destroyed by any kind of
damage, while this is kinda cool its not how I want it.

Currently I have the bomb site Trigger brush outputting to the boxes,
and itll destroy them but nothing stops them from being destroyed
before that. Ideas?

There's another entity for things that blow up on the explosions.
You can find it in the VERC somewhere. I'm too tired to look.

Just select the flag on your boxes (if they are func_breakable) to <span style="color: orange;">Trigger only

If they are props, there should be a flag like that or a "dont take damage" type flag.

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