The detail here is really great! I thought that maybe aluminum foil would work here. I found this paper: https://www.acsu.buffalo.edu/~ddlchung/Materials%20for

The detail here is really great! I thought that maybe aluminum foil would work here. I found this paper: https://www.acsu.buffalo.edu/~ddlchung/Materials%20for%20electromagnetic%20interference%20shielding.pdf https://www.acsu.buffalo.edu/~ddlchung/Materials%20for%20ele... > electrical conductivity is not the scientific criterion for sheilding ... Metals ... function mainly by reflection. > A secondary mechanism of EMI sheidling is usually absoprotion. > The absorption loss is a function of the product σrμr, whereas the reflection loss is a function of the ratio σr/μr, where σr, is the electrical conductivity relative to copper and μr is the relative magnetic permeability. > The reflection loss decreases with increasing frequency, whereas the absorption loss increases with increasing frequency. So it turns out aluminum foil wouldn't actually be much good, with σrμr=.61 and σr/μr=.61. The commercial material listed says it uses copper & nickel: nickel's σrμr=20, copper's σr/μr=1. So my thought here is completely wrong. Who would have figured the commercial product has gone through more thought than my random guesses!