The Design
X1 BladeFins are similar in design to the maker’s original BladeFins, engineered around a monocoque frame and power-plate. The solid internal monocoque is built using high-grade ABS polymers and forms the skeletal structure of the fin, including the low-profile side-rails and the base of the foot-bed.
The in-fill panels are made from the same stiff ABS and are permanently joined by a flexible rubberised polymer, which also forms the distinctive “X” styling on the blade and is used for the upper body of the foot-pocket.
This new design of pocket is slightly taller than that on previous models and has low-friction sections and suction-release holes intended to allow for easier donning and doffing. Its larger profile also allows more room for drysuit boots.
This is a very rigid fin, claimed to have been engineered for divers who employ powerful kicks. The blades are slightly shorter but much firmer than those of most other fins and are said to generate power and thrust when using any finning style.
X1s are supplied as standard with Atomic’s EZ-Lock strap-and-buckle system, where the buckles are attached and released directly from the retaining lugs either side of the foot-pocket. There is raised Atomic livery on the underside of the foot-bed and screen-printed livery on the fin-tip.

In Use
The fins I managed to get my mitts on were, at the time, the only demo pair available in the UK. Because of demand from other testers I had only a limited window of time in which to test them in real-world conditions, and had to settle for inland dive-sites.
I’m telling you this almost as a disclaimer, because I didn’t get to test these fins in anything like a current.
The foot-pockets were a little on the large side when wearing 3mm neoprene booties, and so felt loose. I’m not talking “throwing an apple down the Albert Hall” loose, but they weren’t as snug as I would have liked. This was no problem when diving in a drysuit, because its integrated boots fitted the fins perfectly.
My first impression under water was that these fins were not just rigid but possibly the stiffest pair I have ever encountered, so they took a bit of getting used to.
A few dives into the test, I had learned that by exerting less pressure on the downward strokes when flutter-kicking they actually propelled me faster, with the added advantage that I wasn’t punishing my leg muscles in the process.
I’ve been diving with stiff-bladed fins for as long as I can remember, and the muscles have built up over this time to cope easily with the demand, but the X1s were a step beyond, and I’m sure I didn’t get the best from them when finning like a maniac.
Having said that, how often do you need to fin in this manner? Rarely, I suspect. One advantage of the rigid blades is that there is a definite crispness to acceleration when using short bursts of power.
My preferred style of fin-stroke is the frog-kick, which pushes the displaced water behind the fin and, unlike scissor- or flutter-kicks, doesn’t lift clouds of silt from the seabed when hugging the underwater terrain.
It’s here that the X1s excelled, and although they needed a little effort to get going, once I was moving it felt effortless.
Finning backwards appears at risk of becoming a lost art these days, but it’s a skill that underwater photographers use on virtually every dive to help gain an advantage with composition without disturbing the subject.
In my experience, to execute this operation successfully the fin-blades need to be on the stiff side.
The X1s were perfect in this department, allowing me to select reverse gear at will and effortlessly move backwards as the blades scooped the water forward.
One thing I did notice, regardless of the kicking style or pressure applied, was just how stable these fins were. There was never any sign of twisting as they were pushed and pulled through the water. The blade-tips cupped on the up- and down-strokes, scooping the water off the end with the side-rails channelling it in a single direction.

Pool Test
Two years ago we conducted a group test of fins, (Kickin’ Back the Power, June 2014). To compare 14 models we took them to a swimming pool and, kicking furiously against a fixed line and a set of digital scales, recorded the readings.
Some of the results were a revelation, especially with the split-blade models. What wasn’t surprising was that the best performer was an ever-popular Italian model with a stiff blade (my personal choice too) that produced a reading of 23kg.
When we put the X1s through the same test, I thought my quads and calves were going to explode. Flutter-kicking was hard graft, but the digital display quickly rose to 22kg.
Unfortunately, my little legs couldn’t maintain the effort needed to sustain this level for long, and I had to abort because of cramp.

Rigid fins aren’t for everyone. First, you need the muscle power to get the best from them and, second, you need the stamina. But for those who like to employ a full array of kicking styles and have the legs to do it, generally the stiffer blade rules.
Atomic claims that X1 BladeFins are engineered for powerful kickers, but I found that there’s more to them than that. This is a very stable fin which, when used in a relaxed style, actually appears to need less effort for propulsion.
It’s when applying some muscle that they transform into beasts, providing crisp and formidable performance.
The best analogy I can think of is that this fin is like a high-end Audi RS6. Driving round town, it’s like any other family estate car with good economy, but when you put your foot down you’re into supercar performance with supercar fuel consumption.

CONSTRUCTION Monocoque frame
STRAPS Composite rubber, EZ-Lok buckle system
COLOURS Black, blue, yellow, silver and red

See more fins in Divernet Showcase