Introduction: Rubber straps are not something I've ever particularly liked, having had them on a few watches in the past. Something about the heft of a stainless steel bracelet always appealed to me, particularly on heavier dive watches such that Omega produces. The Seamaster Pro, Planet Ocean, PloProf, and the range of variations of these lines all feature a heavy watch head coupled with a heavy duty bracelet typically in the order of 180-220 grams in weight. This never quite felt right to me on a rubber strap due to the head never quite feeling securely in place and centered as it was with the factory bracelet. Lighter silicone straps tend to slip too easily, while stickier rubber straps held better but became very unpleasant when wet or sweat soaked. When we were searching for an ideal first candidate for a product review, the Isofrane dive straps seemed an interesting choice with somewhat of a cult following. I was keen to understand why owners of high end dive watches were willing to forgo their very expensive and well made stainless steel bracelets for a piece of high tech rubber. Price: I'm going to address this only briefly, because I think it's unlikely to be an issue for Omega enthusiasts. The cost of the strap is $109 including shipping. This is actually a fraction of the cost of an OEM Omega strap, so really it simply isn't a factor if you're considering this as a replacement for your worn original Omega strap, or if you want to try rubber and bought your watch on a stainless bracelet. Comfort: This is a rather interesting aspect of the Isofrane strap, and something that tends to be touted as its most significant feature. Firstly, the increments of adjustment are remarkably fine for a rubber strap, allowing a very precise fitment which is definitely a plus. In addition to that, the Z-shaped flat, elongated tang buckle is remarkably well designed to keep the strap's profile as low and flat as possible at the clasp, with no bulging. The underside of the strap features ridges along its length which gently grip your wrist, giving a great deal of stability, even with a heavy watch head such as the Seamaster Pro chronograph. The interesting result is that the strap effectively grips you by its sides gently, and needs no tightness to create friction and hold your watch in place. In fact, wearing it with the Seamaster Chrono diver, both a forefinger and middle finger can be inserted all the way beneath the strap at the clasp while wearing it comfortably and securely, such is the grip provided by the ridges. Smell: Yes its an odd heading but it needs to be said, this strap smells like bubble-gum. I have no idea why, its not unpleasant, but in fact rather sweet. Trevor's cat took a very keen interest in sniffing and licking the Isofrane strap. It really doesn't smell rubbery like a basketball or anything, its confectionary sweet, and for those who are curious, if you lick it, it doesn't taste like it smells, or like much of anything. Material: The rubber is interesting in and of itself. It has a great deal of friction when rubbing against itself, for example under the keepers, but does not have a sticky feel against skin and other surfaces. It doesn't get clammy or unpleasant when wet of sweaty, and doesn't cause any skin irritation when worn for long periods of time. The material, while thick has a tremendous amount of give and flex to it, and is extremely pliable, but is not particularly elastic or stretchable. It maintains shape well when being pulled through the tang buckle. The material tends to wear well, with no damage showing after two weeks spent being worn in constant contact with the matte aluminium surface of the Macbook Pro and swimming in the ocean. Seventies-ness: The look is part of the desire people have for these old school straps. There's none of this elegant, flush with the case and lugs tapered design you get with the new Cal 9300 and 8500 Planet Ocean straps, this is pure old school. From an era when divers had facial hair, chest hair, back hair, and strapped an oxygen tank on shirtless, wearing a pair of skin-tight swimming trunks with a blood stained knife tucked in the side, Thunderball style. The straight ladder pattern design is utilitarian, simple, and effective. It offers no decoration, just function, and the clasp mirrors this in its well engineered yet completely unembellished nature. The design of the Isofrane would be considered vulgar and uncivilised by the fairer sex, and frankly that's why I like it. Just like the Omega PloProf, the Big Blue, the Seamaster 1000, and the classic Omega divers of that era, its rudeness is part of its desirability and its a perfect match for those big vulgar divers we know and love as Omega collectors. Conclusion: The strap is compatible with any 20mm-24mm watch including both smaller Omega springbars and thicker Rolex drilled lug springbars. It’s durable, comfortable, inexpensive for Omega watch owners, well designed, and harks back to an era treasured by Omega collectors, hitting all the right notes along the way. Go for Orange to make an impact, or blue/black to colour match your dial. Considering the range of rubber straps on the market aimed at dive watches including Omegas Seamaster and Planet Ocean lines, and the pricing of some of the major alternatives including OEM options, the Isofrane strap makes itself an extremely attractive choice and solid investment for any Omega dive watch!