[zamadatix]

If the product doesn't list some form of dB loss (at at least 1 frequency) I assume it's more or less just a standard box. Sometimes that'll be right, sometimes it won't. Some of it comes down to how you use the box as well. If you're feeding un-isolated power in via a big hole in the back then it doesn't really matter how perfect the front is at blocking signals.

I'm surprised their paint can only gave them a 10 dB difference. I've found simply wrapping things in aluminum foil is good for about 40 dB when it comes to Wi-Fi.

[mschuster91]

At least for microwave ovens, with domestic models reaching 1 kW and commercial (e.g. in food) 2 kW, the shielding on these needs to be pretty darn good to make sure that someone standing right next to it doesn't get their body fried. The maximum allowed leakage power density is 5-10 mW/cm² [1], according to a 2004 study even then most ovens barely get up to 1% of the legally allowed emissions limits [2, page 7].

Out of random interest I tested the "put a phone in it and call it" and it didn't work (as did wifi) that's mentioned in [2].

[1] https://www.hea.de/fachwissen/mikrowellen/sicherheit

[2] https://www.sfu.ca/phys/346/121/resources/physics_of_microwa...

[BertoldVdb]

Don't underestimate the dynamic range of a modern wifi transceiver. It is transmitting at ~20dBm and will receive down to at least -80dBm. You need to achieve >100dB attenuation, well beyond what a microwave oven provides.

Even a solid metal box with a few small holes will struggle.