Siroko began as a simple sunglasses brand. Creating our first sports eyewear line – the K2 – made us realize that in cycling and other outdoor sports, clear vision and eye protection are key. Then along came the K3 line and its little sister, the K3s range. Over the years, Siroko has evolved from an eyewear brand to much more, now specialized in clothing, accessories and all kinds of equipment for cycling and other sports. We have been quite busy expanding our portfolio and improving quality across multiple product lines. But finally the time has come to launch a new model of sports eyewear: the Siroko K4 SRX, premium-quality line, including two styles with ZEISS lenses for an extra performance boost.
Granted, we took a rather minimalist approach when it comes to the name, but we simply wanted to honor the previous lines and keep the tradition going. Especially one that has worked so well in the past.
In terms of their size, the Siroko K4 line is somewhere between its predecessors, the K3 and the K3s, but the design, construction and materials used are completely different. Now, let’s take a closer look at all the details of our much-awaited new arrival:
Frame
The K4 SRX models are made of TR90, a material known for its flexibility, lightness and resistance. The K4 SRX frame has been designed to withstand the most demanding conditions, and guarantees exceptional fit and durability without compromising comfort.
In both K4 SRX PRO styles, the frame is made of recycled material from the French company Arkema, known for developing an extremely durable and lightweight high-performance polymer.
Lenses
Most K4 SRX styles feature category 3 panoramic, polarized lenses with an 8%-18% VLT range that protect our eyes from intense sunlight, improve vision clarity and reduce glare.
The ZEISS lenses in K4 SRX PRO styles are panoramic, but not polarized. The SRX Pro Ride Higher model features category 3 lenses and the SRX Pro Dunes model – category 2 (VLT 18%-43%).
Lenses in all models are made of 1.8 mm thick polycarbonate, a resistant material that provides a strong protection against scratches.
All these lenses are interchangeable, which allows you to adapt your glasses to different light conditions, increasing the versatility of the K4 line. You can swap the lenses among all K4 models as well as choose from our extra spare lenses range sold separately: photochromic, clear and anti-fog.
Naturally, all lenses offer full UV protection: UV400 rating is a must for eye safety, blocking harmful UVA and UVB rays.
Ventilation slots
DrySky ventilation system is a set of little slots in the upper part of the lens. It’s essential to keep the lenses clear and minimize fogging, ensuring optimal vision in all weather conditions.
Temples and nose pads
Rubber-covered temples and nose pads guarantee a comfortable and secure fit, preventing the glasses from moving during any activity. The rubber bands on the temples also ensure that the glasses stay in place when inserted in the slots of the cycling helmet.
In addition, the nose pad allows two positions for a personalized fit or increased air circulation to prevent fogging.
The rubber bands from the temples and nose pads can be taken off for washing. These parts can also be interchanged among all K4 models.
Weight
Both K4 SRX and K4 SRX PRO glasses weigh only 33 g. This means they are really lightweight, offering exceptional comfort. You simply forget that you’re wearing them, focusing fully on your favorite sport.
What else is included in the K4 glasses set?
The K4 glasses come in a hardshell case and include a microfiber pouch to clean the glasses as described here, as well as replacement rubber bands for temples and nose pad.
Accessories for the K4 line
K4 OptiClip: This system allows riders to use the K4 glasses with prescription lenses. It’s a simple optical clip that can be attached and removed easily, made of TR90 to ensure lightness and durability.
K4 PhotoChromic: Polarized photochromic lens adapting to changes of light in order to avoid blinding glare. It controls the transmission of light independently and goes from category 2 to category 3.
K4 Clear: Clear, transparent lens. Perfect for cloudy days or at night, providing extra protection against wind or external agents.
K4 ClearFog: Anti-fog lens for cloudy, foggy days or low light conditions.
The spare lenses are sold separately and share the following features with all K4 lenses: made of 1.8 mm thick polycarbonate, with DrySky ventilation system and full UV protection thanks to the UV400 rating.
Teaming up with two giants in their fields – ZEISS, a global leader in precision optics, and Arkema, a pioneer in advanced material development – was the perfect combination that brought to life the K4 line, redefining our standards of performance, comfort and design.
For Siroko, this partnership means offering our customers products of the highest quality as well as learning how the top players in the field work and then putting what we have learned into practice in all the new K4 models. Yes, all of them. Because apart from the Arkema frame and ZEISS lenses, all models share the same features and technical details that make the K4 an ideal choice for any sports activity. And if you’re looking for extra quality and performance, the K4 SRX PRO Dunes and K4 SRX PRO Ride Higher models are the way to go.
