Every question, answered.

That's the reason it's shaped this way. The wide flexible base spreads across cushion or fiberglass instead of needing a level surface, and the fins hold the drink from the sides. Heel into a gust or take a wake broadside and it resists tipping — it flexes back level instead of going over.

Different mechanism entirely. Suction only bonds to smooth, dry surfaces — it can't grip cushion, non-skid, or canvas, and most brands warn against much heel at all. This one doesn't suction to anything; the wide base and the fins do the holding, on wet gelcoat or foam alike.

Measure the bottom, not the rim. A base 2 to 3 inches across settles in here, and the 40 oz Stanley fits — the same size that outgrew most factory console holders.

No. Nothing clamps, mounts, or gets drilled into the boat. It sits on top of whatever's underneath and moves from the cockpit to the sunpad in a second.

Wherever a drink lands: the cockpit bench, the sunpad, the cockpit table, the helm, the swim platform. It doesn't need a dedicated seat or a factory holder built into that spot.

Yes — it works at least as well on hard, flat fiberglass as it does on foam. That's useful right where the older molded holders are the most likely to be too small for a modern tumbler.

Motion is the whole design brief. The base flexes with the roll and brings the drink back level. It resists tipping — it isn't magic, so a direct hard knock is still a direct hard knock — but an ordinary wake rolling through the anchorage is exactly what it's built to shrug off.

Rinse it or run it through the dishwasher. It's one piece of solid molded material with nothing to come apart and nothing for salt or spray to get into.

It's called the Steadi, molded in small runs in Orange, California by Steadi Labs — veteran-founded and patent pending. Every order ships free from steadilabs.com, with 30 days to change your mind.

Not much on it to break down. It's one piece of solid injection-molded material — no metal fittings, no hinges, no suction seal, no hardware bushings for salt to work into the way it does in a rail-mount holder. Rinse it off with the rest of the boat after an outing and it's ready for the next one, with none of the adhesive backing or rubber gasket that eventually dries and cracks on suction-cup holders left in the sun season after season.

Stemless is the shape it holds best. The fins grip a container's base, and a stemmed glass's actual contact point is the narrow foot of the stem, not the wide bowl above it — narrower than what the fins are built to grip. The stemless insulated wine tumbler that's become the standard sundowner glass aboard settles in the same as a can or a tumbler, and a top-heavy acrylic cocktail cup, sweating within a minute of coming up from the cooler, is exactly the kind of drink this is built to hold through a step across the raft-up.

A koozie solves a different problem. It keeps a can cold and a hand dry, but it does nothing to stop the can from tipping — if anything, a koozied can is lighter on its feet and easier to knock over than a bare one. This holds the can steady from underneath and the sides; a koozie can go right on riding inside it.

Depends on the boat and the day. A couple daysailing usually does fine with two or three moving around the cockpit and sunpad. A boat that regularly hosts sundowners for a full crew, or ties up at a raft-up with guests aboard from other boats, tends to end up with one per regular seat — cockpit bench, sunpad, helm — so nobody's drink is the one left balanced on the rail.

A practical one. There's no measuring a rail or a console bore, no drilling, and no guessing whether it'll fit whatever cup holder the boat already shipped with. It's useful straight out of the box, on a boat that otherwise already has everything.

Nothing special. There's no bracket to unbolt, no suction seal to peel off and store separately, and no hardware to seize up while the boat sits on the hard. Toss it in a locker, a cushion bag, or a bin with the rest of the loose gear, and it's ready to go back out the day the boat splashes again.

Under about 2 inches at the base, a container sits too loose for the fins to hold — the honest floor of the fit range, the same aboard as anywhere else. An espresso cup falls into that gap and is a genuine no-fit, not a close call.

No — and it's worth saying plainly rather than leaving it a surprise at the rail. The base diameter on most handled mugs is actually in range; the handle is what doesn't work, because it lands exactly where a fin needs to close in from the side. A handle-less mug or a lidded travel cup solves it; a handled one is the one honest exception aboard.

Depends what the recess actually holds. Owners of boats with molded-in table wells report them sized for a stock can and not much else — shallow, wider than most cups actually need, with no raised lip to stop a wider base from sliding once the boat heels. And the table is only one seat aboard; this one goes wherever the recess isn't — the bench, the sunpad, the helm, the swim platform.