My wallet has to have RFID cards in them for plant access.
So I got one made out of 100,000 stainless steel threads.
The way they are woven creates a Faraday cage or Faraday shield
and blocks all radio signals.
I was just in NYC and stopped in their shop to pick up another one.
http://www.stewartstand.com/I am sure there are copies on the market, but these have a lifetime
warranty that is unconditional. Just one a phone call and a new
one is on the way, no questions asked.