I have a wallet that’s supposedly shielded and it turned out to be useless. Then I got a jammer card as a marketing gimmick. It doesn’t just shield, it creates interferences. The stronger the EM field the better, to some degree. It actually works flawlessly. At least with my smartphone I can’t read any NFC chip near that card.

If you do not need the nfc cabability of your cards, just his them in front of a bright lamp, see where the cables run and cut the card with a scissor. Apply transparent tape over the cut and you have a privacy respecting card again. It’s what I always do as my bank offers no service to disable nfc.

Personally I think its better to just drill a hole in thr antenna and pay by chip