Why 13.56 MHz Is the Only Frequency That Matters

If you have shopped for RFID protection, you have probably seen products advertised as blocking all frequencies, 125 kHz to 13.56 MHz, or even higher ranges. The marketing is technically accurate. It is also irrelevant for almost every traveler.

Here is what actually matters.

What you carry runs on 13.56 MHz

The card-sized things in your wallet that hold value or grant access almost all use the same frequency band. That includes:

  • Contactless credit and debit cards (Visa, Mastercard, American Express, Discover)
  • Most modern hotel keycards
  • The chip layer in e-passports issued from 2007 onward
  • Public transit cards in major cities (London Oyster, NYC OMNY, Tokyo Suica)
  • Mobile wallet hardware secure elements (the same standard, in your phone)

One frequency. One protection target. The shielding strategy follows from that.

What 125 kHz protection is for

The lower frequency band, 125 kHz, is used for older proximity badges. Office building entry cards from the early 2000s. Some hotel room cards in older properties. A handful of warehouse and industrial access systems.

If you are an enterprise security manager, 125 kHz still matters. If you are a traveler carrying cards and a passport in 2026, it almost never does.

Why we focus on the right target

A shielding material that blocks every frequency from 125 kHz to 13.56 MHz adds weight, thickness, and cost without adding traveler-relevant protection. Alpine Rivers® products are tuned to defend against the threat travelers actually carry, not the marketing copy on a competitor's box.

What tuned means in practice

Our shielding uses a multi-layer barrier specifically engineered for the 13.56 MHz band. That layering is what allows our sleeves to stay slim enough to fit a standard bifold wallet, and our money belts and neck wallets to stay flat enough to disappear under a shirt.

We will not advertise blocking frequencies that have nothing to do with the cards in your pocket. We will tell you exactly what we protect against, and we will keep the gear small enough that you will actually use it.

Curious how the shielding works at the physics level? Read How RFID Protection Works.