If you’ve got a helmet with a magnetic buckle, the chances are pretty much 100% that it was made by a little-known German company called Fidlock. Fidlock’s Snap helmet buckle uses a mushroom-shaped stub on one side that meshes with a sliding latch on the other side. A magnet pulls the two halves of the buckle together — and you just have to get the pieces close to each other. To undo the buckle, you slide the halves sideways.
It’s an ingenious (and secure) system, and given the Snap buckle’s increasing popularity in terms of spec on new helmets, it’s clearly gaining favor on the consumer side, too.
Fidlock has a surprisingly diverse range of products (I strongly suggest you take a look at the company catalog), and the company recently adapted that same mechanism to a novel cageless water bottle system called Twist. There’s a low-profile base that bolts to your frame as usual, and then a dedicated bottle that’s offered in both 600mL and 450mL sizes.
There’s even a Uni Connector (with a Boa dial!) that will allow you to attach nearly any bottle to a Twist base, as well as a Uni Base that uses rubber straps instead of the usual bolt-on attachment.
Regardless of the combination, the way the base and bottle attach to each other is the same. Whereas the Snap helmet buckle just uses one of those mushroom-shaped stubs, Twist uses two. As with the helmet buckle, all you have to do to securely connect the two pieces together is hold them near each other. To remove the bottle, you — go figure — twist the bottle on the base.

Without question, it’s very clever, and just like the Snap helmet buckle, it’s admirably secure. Whether on smooth roads, rough gravel, on trails, or whatever, I never lost a Twist bottle, which I most definitely can not say about every other cageless bottle system I’ve used in the past.
And given that Fidlock has seemingly cracked the code on cageless bottle security, there are the usual advantages to the format in general. For travel bikes, the low-profile base makes it easier to stuff an S&S or Ritchey Breakaway bike into an airline-legal case. And for cyclocross, it means you can have a bottle at the ready for training rides or warm-up laps, but then quickly ditch it without having to worry that an empty cage will snag your jersey. Trail riders on full-suspension bikes with limited clearance may find that the Twist allows them to carry more water than usual, too.

Weight-wise, it’s basically a wash. A complete Fidlock Twist 600 bottle-and-cage set comes in at 121g, which is virtually identical to a standard Specialized Big Mouth bottle (78g or 90g, depending on size) and most modern fiber composite cages.
A neat idea, but one without a clear purpose
The problem, however, is that the Fidlock Twist seems to create more problems than it solves.
The twist motion itself is easy enough, and it takes no time at all to adapt while in the saddle. However, getting the bottle back on the base is a different story. Although the “just get it close” concept sounds good in theory, in practice, it’s more like “just get it close … but make sure the two mushrooms and sockets are reasonably well aligned first — oh, and make sure the bottle is rotated the right way, too.”

In some ways, I equate it to the infotainment systems on many modern cars. Sure, it’s great that you’ve integrated the volume control into a high-definition full-color touchscreen. But you know what I really want? A knob I can grab without looking for it.
Fidlock also only offers the Twist in a single configuration, meaning you have to rotate the top to the right when it’s mounted on the down tube, but to the left if it’s mounted to the seat tube. The bottle itself is merely ok, too. The top is nice enough — easy to open and close, and leak-free — but the body is hard to squeeze. And since the Twist is a proprietary platform, you’re stuck with dedicated Fidlock bottles.
Granted, Fidlock does have that universal Boa-equipped adapter, but that’s more likely to be used for stuff like fuel bottles and other oddly-shaped bike packing gear.

Cost-wise, the Fidlock isn’t horrible, but it’s not exactly cheap, either. A complete kit with one base and one bottle costs US$40 / AU$60 / £31 / €30; individual bottles are roughly the same as usual. Given the complexity involved, it’s a pretty reasonable figure.
But at least for me, Fidlock is going to have to make a stronger case than just novelty for the Twist bottle to make sense, especially when something like the Bontrager Quick Connect bottle mount offers similar niche benefits without any of the downsides (and yes, I’ll have a review of that soon), plus the fact that there are already plenty of excellent side-access cages available for frames with tight clearances.
Until then, it’s back to regular bottles for me — and volume knobs.