USB Data Blocker

Overview

A USB data blocker — nicknamed a "USB condom" — is a tiny adapter that sits between your cable and a charging port and physically disconnects the data pins, leaving only the power lines connected. The result is that a device can draw a charge but cannot exchange any data with whatever it's plugged into. It's a simple, passive defence against "juice jacking," where a compromised or malicious USB port tries to read from or push malware onto a connected device.

For a Bitcoiner, the value is being able to top up a phone or hardware wallet from an untrusted source — a public kiosk, someone else's computer, an unknown charger — without exposing a data channel. It's cheap (around $12), pocketable and needs no setup. The honest caveats: it protects only against data-line attacks, not against a device you already trust or against wireless threats. Some blockers can limit charge speed since fast-charge negotiation sometimes uses data lines, though many modern units mitigate this.

Buy it if you ever charge devices from ports you don't fully trust and want a simple hardware guarantee that no data can pass. It's a sensible, low-cost addition to a travel and self-custody kit, not a substitute for broader device security.