Review of the Straight FKM Rubber Strap by Helvetus

I was sure I had FKM rubber figured out. I have worn plenty of these straps, and I thought the formula was set in stone. Then a black strap from Helvetus landed on my desk. Angled holes, optimal thickness, two finishes on one strap, and a 4mm taper that makes it disappear on the wrist. I wore it for two months and I am still finding things to like. Here is the full review.

Nenad Pantelic • September 2, 2026

Full review

I never looked to Switzerland for straps. Watches, sure. Movements, cases, dials, that's their territory. But straps? For those I always looked elsewhere: Italy, Spain, and Singapore for leather, the UK and US for nylon, Asia for rubber. Man, was I wrong.

One shipment later, this Swiss product made me realize they do straps great, too. I have a soft spot for FKM rubber. We covered the material in detail before, and since then I have worn more FKM straps than I care to admit. After a while they start to blur together: same smooth surface, same thickness, same buckle.

This one didn't blend in. Helvetus did a long list of small things differently. Individually, none of them is a big deal. Together, they add up to a strap I kept wearting. Let's go through them.

Technical details

Brand	Helvetus
Width	22mm
Tapering	4mm (22mm to 18mm)
Length	125mm + 75mm
Material	FKM rubber; hypoallergenic
Lug type	Straight end
Color	Black
Finishing	Smooth central ridge; grainy sides
Underside	Wave pattern
Buckle	Stainless steel; Brushed finish
Keepers	One fixed (notched), one floating
Spring bars	Integrated quick-release spring bars
Warranty	Lifetime

The strap comes in 20mm, 22mm and 24mm widths. Mine is black, but the collection includes navy blue, white, green, grey, red and more. You can also pick the buckle finish: silver, black, gold or rose gold.

In short, with that many combinations, you can match it to pretty much any watch in your box.

Company and ordering

Helvetus started as a project of three students who were deep into the luxury watch scene. They began at local craft markets with a handful of suppliers, and today they are one of the bigger names in aftermarket straps. Their catalog covers more than 86 strap styles for over 16 watch brands. If you own a Rolex, Omega, Tudor, IWC, Hublot or Panerai, chances are they make a fitted strap for it.

Along with those fitted straps, they offer universal straight-end rubber straps, which is what we have here. Their rubber straps are made from either vulcanized or FKM rubber.

Every order comes with what they call the Helvetus Excellence Service: lifetime warranty, hassle-free returns and free worldwide shipping. The webstore is easy to get around, and checkout is quick. Pro tip: they run a bundle offer, so if you buy two or three straps for the same watch you get 15% or 25% off.

Design and Materials

At first glance, this is a classic ridged FKM rubber strap. But the ridge is not as pronounced as on some other FKM straps I have worn. It is subtle and unobtrusive, so it adds some visual interest without fighting the watch head for attention. I think this was the right call.

Now for the small detail that I love. The central ridge is completely smooth, while the sides of the strap have a grainy, almost sandblasted look. It is barely visible. It's one of those things you notice only when you zoom in, and then you can't unsee it. This is something I really appreciate. Multiple finishes on a single strap is a sign of a premium product, and here it is done with restraint.

The buckle holes are sloped. When you fasten the strap, the tang of the buckle sits at an angle that follows the curve of the wrist and doesn't stress the rubber. This is a feature I wish more rubber straps had. I have a few FKM straps where the tang sits straight up and pulls on the hole, and after a year you can see it.

Flip the strap over and you'll find a wave pattern on the inside of both pieces. These ridges keep the strap from sticking completely to the wrist, and they also channel out sweat and water.

The strap tapers from 22mm at the lugs to 18mm at the buckle. That's a 4mm taper, which is more than you get on most rubber straps. The overall thickness is a bit thinner than a standard smooth FKM strap. It is not delicate, though. It is thin enough to be comfy and thick enough to support most watches. This is exactly the balance I look for in a rubber strap, and it's surprisingly hard to find.

The buckle is heavy-duty, brushed and made from stainless steel. There are two keepers. The first one is held in place by integrated side notches on the shorter piece, so it can't slide. This is a smart detail, because the first keeper is the one responsible for keeping the fastened strap secure. The second keeper floats, and its only job is to keep the tail end tidy. I have lost count of the straps where the first keeper wanders halfway down the strap by lunchtime. Not here.

A small story. I wore this strap in the office, and a colleague of mine, a Doxa guy who knows all about my strap obsession, asked me about it. I handed him my Seiko, he put it on, and he was impressed with how it wore. Coming from someone who lives on a bracelet, that says something.

The strap is equipped with quick-release spring bars, so you can swap it without any tools. The only nitpick I have is that the bolt-action tips are sometimes visible when I wear the watch. Small thing, but I noticed it.

Comfort and Durability

Comfort is fantastic. The material is pliable and supple, and the strap conforms to the shape of the wrist with no effort. There are no hot spots and no places where it digs in. It is fairly slim in profile. Most days I forget I am wearing it.

The taper to 18mm makes a real difference here. There is no big bulge on the underside of the wrist, so you can move your wrist freely. And the rubber itself feels nice against the skin. It is not sticky or plasticky, just right.

As with most FKM straps, there was no break-in period. It was comfy from the first wear.

After two months, there are no signs of damage or wear. On some older FKM straps I got shiny spots where the rubber rubs against shirt cuffs, but nothing like that so far on this Helvetus.

The only long-term issue I've found is that the underside ridges collect gunk, salt and whatever else builds up over the day. When I take the strap off, I can see some white residue in the grooves. A quick rinse under the tap fixes it, but it's something to keep in mind.

Initial Usage Very comfortable from the first wear. Pliable, slim, and the taper makes it wear even slimmer. The small details, like the smooth ridge and grainy sides, make it feel premium.

One month of use Still great. No stretching, no shiny spots, nothing loose. The quick-release spring bars are still sturdy. A bit of dried out sweat in the underside grooves, but a rinse takes care of it.

Two months of use Still great. Looks and feels like it did on day one. If it stays like this, it will last for years.

Compatibility and Pairing Recommendation

This is a black rubber strap, so it goes with everything. Divers and sports watches are the obvious pairing, but it works just as well on field watches and chronographs.

It fits perfectly with my spartan-looking watches, and, of course, with whatever I happen to be wearing on a given day. If you want something less serious, Helvetus has plenty of colors to choose from.

Price and Value

The Straight FKM Rubber Strap is available directly from the Helvetus website, where you can select the width, color and buckle finish.

At the time of writing, the strap is listed at $99, down from the regular price of $139. That puts it in the premium tier of FKM straps. Shipping is free worldwide, and the strap comes with a lifetime warranty. They are so confident in their product that they are willing to offer this kind of support, and that counts for something.

So, is it worth it? If all you need is a black rubber strap, there are cheaper options that will do the job. But if you appreciate the details, the angled holes, the fixed first keeper, the multiple finishes, the 4mm taper, then this strap delivers where the cheaper ones don't.

Closing words

Call me old, but I think that the best straps are the boring ones. Not boring to look at, but boring to live with. No surprises, no frustrations, no reasons to take them off. You put them on in the morning and forget about them until you take the watch off at night.

This Helvetus is that kind of a strap, and I mean it as the highest compliment.

I have had it for two months. Initially it was great, after one month... it was great, and now, after two months... man, it is still great. That's all I really want from a strap.