Only the blade-free ones. TSA guidance permits multi-tools without a knife blade in carry-on baggage and prohibits any multi-tool that contains a blade, whatever its length. So the honest answer is that some multi-tools are carry-on friendly and most are not.
Manufacturers use the phrase to mean a model built with no knife blade, usually replacing it with a file, a pry bar or an extra driver. That is a real product category, not marketing language, and it exists because the blade rule is absolute.
What the phrase cannot mean is that a tool is guaranteed through a checkpoint. TSA states that the officer at the checkpoint makes the final call on every item, so no manufacturer can promise passage.
Open every implement and look for a cutting edge. Some tools hide a small blade behind a saw or a file, and some carry a blade you would not think of as one, such as a wire cutter with a sharpened jaw.
If in doubt, it goes in the checked bag. The cost of being wrong is losing the tool, and surrendered items are not returned.
Most frequent flyers who want a tool in the cabin buy a dedicated blade-free model and leave their full-featured tool at home or in checked baggage. It is a cheap way to stop the question arising at every trip.
Everything in our multi-tool range ships from our Woodlawn, Virginia warehouse. Check each product's specification for whether a blade is included before you buy for travel.
This page is provided for general informational purposes only and does not constitute legal advice. Knife laws vary by state, county, and city, change frequently, and are subject to interpretation by courts and law enforcement. Knives Now is a retailer, not a law firm, and this summary should not be relied upon as a substitute for consulting a licensed attorney in your jurisdiction or reviewing the current text of the applicable statute. Before purchasing, carrying, or shipping any knife, confirm current local, state, and federal law for your specific situation, including any restrictions on carry location, blade length, or knife type. Knives Now makes no warranty as to the completeness, accuracy, or current applicability of the information on this page and disclaims all liability for actions taken in reliance on it.