Sure do, Amazon like any mass focused marketplace with little to no oversight serves as a cheap entry point and breeding ground for knockoffs and inferior “signal blocking” products that make claims that can’t back up. Might be able to buy two small bags for $10 but they will fail very quick. The confusion is that RFID blocking materials and approach is the same as an actual Faraday cage or bag which it’s not. Many radios to block at various frequencies- buy slnt.com for guaranteed success and style