Every question, answered.

That's the whole reason it's shaped this way. A topper-and-comforter stack swallows a narrow base; the wide flexible footprint spreads across it instead of sinking in, and the fins keep the drink from rattling loose when the bed shifts. Push it off level and it settles back.

Yes, and that's the exact gap it's built for. It sits on top of the bed itself, not on a rail or a frame, so it doesn't care how high the mattress sits or what the frame underneath looks like. Whatever surface you're on, the base goes with you.

Measure the bottom, not the lid. A base 2 to 3 inches across fits — the 40 oz Stanley does. Handled mugs don't; the handle gets in the way of the fins.

Yes — soft, shifting cushions are exactly the terrain it's built for. The wide base spreads across the cushion instead of tipping with it, and settles back level each time someone else sits down or gets up.

It works at least as well on hard, flat surfaces. On a desk that's already crowded with a laptop and a charger, the wide footprint and the grip are what keep an elbow bump from finding the keyboard instead of the desk.

No adhesive, no Command strips, nothing the housing handbook has an opinion about. It just sits on whatever surface you set it on — bed, futon, desk, floor — and picks up when you move.

It's one piece of flexible material with nothing to snap or unclip. It packs flat in a drawer or a tote with everything else and comes right back out for next semester.

That's closer to normal use than a stress test. A roommate dropping onto the mattress, a backpack landing next to it, someone climbing the ladder — the base flexes with the mattress and brings the drink back level after. It resists tipping, not a direct hit; a foot planted straight on it is a different story, but a roommate flopping down nearby is exactly the kind of jostle it's built to shrug off.

Rinse it in the hall bathroom sink or run it through a dishwasher if your building has one. It's one piece of material with nothing to come apart or trap a spill.

It's called the Steadi — molded in small runs in Orange, California by Steadi Labs, veteran-founded and patent pending. Orders ship free from steadilabs.com, with 30 days to decide it's earned a permanent spot in your room.

Base width is what decides it, not the brand. A Yeti Rambler 20 or 30 oz tumbler stands on a base about 2.75 inches across — solidly inside the 2 to 3 inch range the fins are built for. The Stanley just gets asked about most because it's the one a campus survey found more than half of students already own.

It's one piece of injection-molded flexible material with no hinge, spring, or clamp mechanism inside it to wear loose over time. There's nothing that fatigues the way a clip's spring-loaded jaw can — the same material gripping a can freshman year is still doing the gripping senior year.

The base is what actually touches the comforter or rug, not the drink — condensation collects on top of the base and wipes off in a few seconds, so it isn't soaking into fabric the way a sweating can set straight on a duvet would. If a full drink does go over, there's no seam or pocket in the material for it to sit and stain in afterward.

Fit is about base width and shape, not about hot or cold — a can, an iced coffee, and a lidded hot drink are all just a bottom inch that either fits the fins or doesn't. A handled mug — the dorm Keurig or tea kind — doesn't work, because the handle lands right where a fin needs to close around the base. A handle-less travel tumbler or camp-style cup within the 2 to 3 inch range settles in the same way a can or bottle does.

It's small, flat, and useful the first week in the room — no assembly, no bed frame or rail it has to match. It works before you even know whether the room ends up with a loft, a futon, or neither, which is exactly the uncertainty a move-in gift has to survive.

One moves with you — it isn't mounted to anything, so it goes from the mattress to the desk to the futon in the time it takes to pick it up and set it back down. If movie nights regularly pack four or five people onto the futon and the rug at once, a second one is a reasonable buy for that specific overlap, so a drink doesn't have to travel across the room whenever someone needs the one that's already out.

Depends on what you actually use it for. A rail-hung holder only works where there's a rail to clamp to — typically a narrow three-quarter-inch to one-inch range — and only accepts cups under about 3.15 inches with no handle, so it does nothing on the mattress itself, the futon, the desk, or the floor. A wide, flexible base isn't picky about the rail or the frame, so the two solve different, narrower problems; there's no reason not to use both if the rail one already earns its spot on the bed.

A full 40 oz tumbler loaded with ice is genuinely top-heavy — most of the weight sits high above a base that's narrow relative to the tumbler's height. The fins grip that base by the bottom inch regardless of how full it is, and the wide, flexible footprint spreads across the mattress or comforter instead of letting a tall, heavy object sink a point into it. That combination resists tipping on a surface that's already uneven; it doesn't change the physics of a top-heavy tumbler, it just gives it a footing the mattress alone doesn't.