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Faraday cloths work!
Sides must be sealed!

Super HOT spot inside my house where the smart meater is located on the outside wall.
I used wide painters tape to seal the edges. Without which the EMF readings were still HOT!

House paint containing lead also works.

The one I purchased isn't currently available, however, this one has reviews with the same results I achieved,
and a larger piece of fabric.

https://www.amazon.com/dp/B0CH8XHXZT/ref=sspa_dk_detail_0?pd_rd_i=B0CH8XHXZT&pd_rd_w=G0vGx&content-id=amzn1.sym.8c2f9165-8e93-42a1-8313-73d3809141a2&pf_rd_p=8c2f9165-8e93-42a1-8313-73d3809141a2&pf_rd_r=3NA8NH9CP7JE6SP270DW&pd_rd_wg=rkYHe&pd_rd_r=3c7d7193-def4-4658-8625-9e166a6917e8&s=home-garden&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw&th=1

Check out the reviews for tips.

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