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Two inflatable PFDs, and the real difference between a vest and a belt pack

Two inflatable life jackets crossed my desk this month, both from Onyx, both Coast Guard approved, priced within ten dollars of each other. I almost skipped this one, since close pricing usually means there isn't much of a story. There is one here, but it isn't about price.

PFDPriceTypeBuoyancyInflation
Onyx A/M-24$119.99Vest, fits 30–52" chest22.5 lbAutomatic or manual
Onyx M-16$109.99Belt pack, adult universal17 lb (26.5 lb with oral top-off)Manual only

The A/M-24 is a standard vest-style inflatable: it inflates and stays where it is, on your torso, whether the trigger fires automatically on immersion or you pull the manual cord yourself. The M-16 is a belt pack, worn deflated at your waist. When it inflates, it becomes a flotation collar you then have to pull over your head yourself, which is how every belt-pack inflatable works, and it means the belt pack only does its job if you're calm enough and strong enough a swimmer to do that correctly after an unexpected fall in the water.

That's also why neither of these is the right choice for a teenager just starting out, or for anyone who isn't already a confident swimmer. The Coast Guard doesn't approve inflatable PFDs, of either style, for use by anyone under 16, and it specifically advises against them for non-swimmers and less experienced swimmers regardless of age, because they only provide flotation after they've inflated, not the instant you hit the water. A standard foam life jacket is bulkier and less comfortable, and it's still the right choice for a beginner, a non-swimmer, or a kid.

So the honest comparison here isn't "which is the better deal," since $10 apart isn't a real gap. It's "which one matches what you actually are on the water." A confident adult swimmer who wants the lowest possible profile might reasonably choose the M-16's belt pack. A confident adult swimmer who'd rather have flotation that stays on without a second step might choose the A/M-24 instead. If you're under 16, a non-swimmer, or still building the skill and confidence this site exists to teach, the answer isn't either of these: it's a standard foam PFD, the one that doesn't ask anything of you to work.

For the business: marine retailers & sailing schools If your shop or your program sells or issues inflatables to anyone under 16 or to a beginner class, that's worth a second look against the manufacturer's own age and swimmer-experience guidance, not just the price tag.

Can a teenager or a new sailor wear an inflatable PFD instead of a foam one?

No. Inflatable PFDs, vest or belt pack, aren't approved for anyone under 16, and the Coast Guard doesn't recommend them for non-swimmers or less experienced swimmers of any age, since they only provide flotation after inflation. A standard foam life jacket floats you the instant you're in the water, which is what a beginner needs.

What's the actual difference between the vest and the belt pack?

The vest inflates and stays on your body. The belt pack inflates into a separate flotation collar you then have to pull over your head, which only works if you're a confident swimmer able to do that calmly after an unexpected fall in the water.

Is the belt pack actually cheaper?

Barely, at full manufacturer price it's about ten dollars less than the vest. The real trade-off between them isn't cost, it's who each one is safe for.

Sources

No affiliate or sponsorship relationship with Onyx. Prices and specs checked directly against manufacturer product pages, current as of this edition's publication date; check current pricing before buying, as it changes.

Christopher Ross

Christopher Ross

Christopher runs thisismyurl.com, a WordPress, LMS, and web infrastructure practice, and founded Sail Commons in 2026 as a free, open source approach to sailing education. He writes and curates every edition.

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Christopher Ross

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I'm a sailor who builds learning systems, and I founded Sail Commons to open sailing knowledge up.

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