K-Mask

K-Mask

S
£10.50 GBP
Sale price  £10.50 GBP Regular price  £30.00 GBP
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K-Mask

K-Mask

£10.50 GBP
Sale price  £10.50 GBP Regular price  £30.00 GBP
KMSK02

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Size

Key Features

Viral Filter Nanofibre Infrared K-Mask:

  • The K-Mask comes with a Nanofibre K-Filter - with filtration rating 99.6%* - effective for 200 hours before filter needs replacing.
  • In-built filter slip pouch, with easily changeable filters for continued protection.
  • The K-Mask and K-Filters can be baked in the oven at 60 degrees, during their 200 hour period to kill all trapped bacteria and viruses, offering added security.
  • Made from KYnergy Infrared fabric that helps to thermoregulate whilst wearing. The infrared also offers a cooling effect to breath when inhaled.
  • Adjustable straps with velcro fastening that fit around the back of the head and nape of the head/neck for a comfortable fit, suitable for long periods of time.
  • Extended sides offer pressure balance, so that it forces the inhaled and exhaled air through the viral filtration, even with use at high exertion, such as in Sport, or during coughing or sneezing.
  • The nose has a wired pinch bar so the wearer can ensure a close, comfortable fit, with attractive leather detailing to the front.
  • The close fit reduces the occurrence and severity of glasses steaming whilst both are in use.
  • The K-Filter is made from biocompatible hydrophobic material which is elastic and electrostatic, meaning they are highly breathable and flexible, and will not become wet with water vapour from breathing. This also reduces the carbon dioxide re-breathing occurrence.
  • Mask is washable at 30 degrees.
  • Separate replacement filters available here.

Description

The KYMIRA K-Mask, with the integrated Nanofibre K-Filter, is designed to protect you from viruses, bacteria and environmental particulates, with a 99.6%* filtration efficiency that is rated as one of the best in the world. You can use the filters in the K-Mask or a mask of your choosing with a filter pouch and they can be cut to size without harming the technology to help fit into any mask. 

Available individually or in 5 packs, 17% discount on 5 pack cost .

Looking to help during the pandemic, KYMIRA researched and adjusted one of its existing technologies, the electrospun nanofibre material, with partner Radical Fibres. 

The Nanofibre K-Filter:

Using a triple sandwich layer nanofibre combination, the K-Filters have been designed as a re-usable, world class filter that will protect you and those around you.

Layer 1: Nanofibres capture viruses, bacteria and pollutants via electrostatic attraction. 

Layer 2: Activated carbon layer traps environmental pollutants. 

Layer 3: Nanofibres capture viruses, bacteria and pollutants via electrostatic attraction.  

The filters have been independently tested to ASTM F2100, ASTM FT101 and EN 1486 standards, certifying the 99.6% filtration rating*. The K-Filter offers its protection for 200 hours, and for particles as small as 0.03 microns. The effectiveness of the filtration level is due to this microscopic level of protection offered by the electrospun nanofibres, that ionically attract the particles before trapping them within the filter layers. To contextualise this, the Covid-19 virus has a particle micron size of 0.06-0.5, and bacteria have a particle size of 0.3 microns. Healthcare workers on the front line have so far been using N95 rated masks that have a particulate protection size of 0.3 microns; so  you can feel confident in their protection when using the K-Filter.

The nanofibres within the K-Filter are made from biocompatible hydrophobic material which is elastic and electrostatic, meaning they are highly breathable and flexible, and will not become wet with water vapour from breathing. This also reduces the carbon dioxide re-breathing occurrence that is a problem among medical grade respirators.

The KYMIRA K-Filter has proven itself to be one of the most effective air filters in the world.

The K-Mask:

KYMIRA has created the K-Mask: more breathable, more comfortable, and more effective, using cutting edge design and technology. 

The K-Mask is designed to house the Nanofibre K-Filter and is made from KYMIRA Kynergy® infrared fabric. This fabric offers the wearer temperature-regulation, due to its efficiencies in cellular excitation and enhanced circulation. The infrared fabric itself supports the wearer to cool or warm, and provides a cooling effect as you inhale, helping you to stay comfortable during use.KYnergy®infrared fabric withCelliantis safe to use, designated a class 1 medical device by the FDA, and CE marked.

The fit and design of the K-Mask is second to none. Available in sizes small, medium, and large, the mask is designed to fit close to the wearer, high up on the nose and wrapping around the cheeks towards the ears to provide greater protection to and from the wearer. The extended sides offer pressure balance, so that it forces the inhaled and exhaled air through the viral filtration, even with use at high exertion, or during coughing or sneezing. This makes the mask ideal for not just everyday activities, but for work, travel and playing sport too. The nose has a comfort strip underneath, and a wired pinch bar so the wearer can ensure a close, comfortable fit, with attractive leather detailing. The straps fit around the head, fastening on the crown of the head, and at the nape of the neck, providing comfort for long use that does not put pressure on the ears. The adjustable velcro fastenings and stretchy infrared fabric ensure the fit is close to the individual wearer. The close fit offers another benefit, it reduces the occurrence and severity of glasses steaming whilst both are in use. 

*The Nanofibre K-Filter has been independently tested to ASTM F2100, ASTM FT101 and EN 1486 standards. PM2.5 particulate efficiency tests have been completed under ASTM F2299, and bacteria filtration testing under ASTM F2101. N95, which is determined by the seal of the mask to the face will need to be repeated for the washable replacement filtration mask. The nano fibres have been N95 evaluated, tested, and approved by NIOSH as per the requirements in 42 CFR Part 84. In Canada, the United Kingdom, the European Union, Australia, New Zealand and Japan, it is designated as a Class 1 Medical Device. EN149– Filtering face piece and particulate respirators. PM2.5 particular efficiency tests under ASTM F2299, and bacteria filtration testing under ASTM F2101. PM2.5 pollution is particularly harmful since it can penetrate human bronchi and lungs owing to the small particle size. Hence, long-term exposure to PM2.5 increases morbidity and mortality. 

Infrared Benefits

  • Increased local blood circulation
  • Increased tissue oxygenation - by up to 20%
  • Increased cellular metabolism
  • Enhanced energy production
  • Temporary pain relief - experience a 25% average reduction in pain naturally
  • Accelerated recovery rate - from physical exertion, injury and surgery
  • Reduces Inflammation
  • Injury prevention - 80% average reductions in soft tissue injuries via muscle priming
  • Temperature regulation - warms & cools to suit your needs - clothing stores thermal energy 63% longer than standard fabrics when used as a base layer - fabrics dry 65% quicker than average fabrics
  • SFP35+ rating
  • Antimicrobial

Best Use

Wear the K-Mask with internal K-Filter, whenever you are in public, or in large groups of people - to protect yourself, and those around you.
Change the filter for a fresh K-Filter replacement at least every 200 hours, for continued 99.6%* protection from viruses, bacteria and environmental pollutants.

The masks and filters can be baked in the oven at 60 degrees, and this will ensure that all trapped virus and bacteria particles are killed. The mask itself is also machine washable at 30 degrees, so it can stay looking fresh and clean (please note the filters should not go through the washing machine).

The infrared is continually beneficial, does not wear off with use, and the products are safe to use continually - KYMIRA® Products with Celliant® are determined to be Medical Devices

Fabric & Care

FABRIC COMPOSITION

  • 51% KYnergy Polyester
  • 35% Polyester
  • 14% Spandex

CARE INSTRUCTIONS

The Nanofibre K-Filter offers the wearer 200 hours of viral, bacterial and pollutant filtration protection. Once this time period is completed, the filter can be replaced with a fresh filter, and the protection will continue.

The K-Masks and K-Filters can also be cleaned and reused during this 200 hour period. The masks and filters can be baked in the oven at 60 degrees centigrade for 15 minutes and this will ensure that all trapped virus and bacteria particles are killed. The mask itself is also machine washable at 30 degrees centigrade, so it can stay looking fresh and clean (please note the filters should not go through the washing machine).

  • Wash at 30C/86F
  • Do not tumble dry

Reviews

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Why IR50? Our Most Advanced Recovery Technology

- Boosts circulation to deliver oxygen and nutrients where your muscles need them most.

- Accelerates lactic‑acid removal, reducing soreness, stiffness and fatigue after intense training.

- Supports cellular metabolism + repair, helping you recover faster between sessions.

- Reduces inflammation and discomfort associated with high‑load training and repetitive stress.

- Temperature‑regulating infrared fabric keeps you warm or cool as needed, ideal for all‑day wear.

The technology behind the textile

The science inside KYMIRA’s infrared performance baselayers

KYMIRA’s patented KYnergy® infrared textile embeds a matrix of bioceramic minerals into each fibre. These minerals capture body heat and convert it into far-infrared (FIR) light in the 6–14 µm range, supporting circulation, oxygenation, energy production and recovery.

How it works

From body heat to biological signalling, the technology is designed to support the body throughout movement and recovery.

01

Energy conversion

Body heat is absorbed by the mineral matrix and re-emitted as FIR light in the 6–14 µm range.

02

Nitric oxide activation

FIR exposure is linked to increased nitric oxide availability, promoting local vasodilation and improved micro-circulation.

03

Enhanced oxygen delivery

Independent tcPO₂ studies show that FIR garments raise tissue oxygenation, supporting aerobic energy pathways at a lower physiological cost.

04

Mitochondrial efficiency

FIR supports cellular energy and ATP production, helping sustain output and reduce the sensation of fatigue.

05

Biological signalling

Exercise studies show FIR garments activate signalling pathways related to mitochondrial biogenesis and angiogenesis.

06

Thermal balance

FIR helps stabilise micro-temperature during and after exercise, while the textile maintains breathability and moisture management.

Why it matters for performance

Designed to support sustained output, movement quality and rapid in-session recovery.

Power, strength & endurance

  • Improved oxygen delivery and faster aerobic system activation.
  • More efficient ATP production and reduced oxygen consumption requirements.
  • Support for sustained intensity, total work output and neuromuscular efficiency.

Movement quality

  • Enhanced local circulation and oxygenation help prime muscles for movement.
  • Support for mobility, flexibility, control and stability during high-speed movements.
  • Greater acute skeletal muscle adaptive responses during exercise.

Rapid in-session recovery

  • Supports the removal of fatiguing metabolites produced during exercise.
  • Helps moderate soreness and inflammatory responses.
  • Supports repair between efforts and training sessions.

Why KYMIRA supports injury prevention

Consistent movement starts with muscles that are prepared, oxygenated and able to maintain efficient mechanics under fatigue.

Enhanced circulation and oxygenation help prime muscles to be stronger and more flexible, supporting mobility and consistent movement patterns. Efficient muscular contraction, cellular energy support and reduced fatigue may help limit compensatory mechanics. Temperature regulation helps maintain muscle compliance, while recovery mechanisms support lower cumulative tissue stress between sessions.

Performance technologies should complement, not replace, a progressive training plan, appropriate warm-up, recovery, and professional medical advice where needed.

Size guide

The size charts below detail the relevant sizing or points of measurement for all of our products. Our garments do not need to be tight and against the skin for our infrared technology to work, so we suggest fitting to your personal preference. If you are looking for a looser fit, then size up from the guide's suggestions.

Unisex sizes

SizeXSSMLXL2XL
K-Mask: Head circumference (UK only)45cm – 55cm50cm – 60cm55cm – 65cm
Socks & sleeves foot size (UK)3 – 56 – 89 – 1114 – 16
Socks & sleeves foot size (USA)5 – 67 – 1011 – 1415 – 17
Socks & sleeves foot size (EU)35 – 3839 – 4243 – 4749 – 52
Socks & sleeves calf size (all)27cm – 32cm34cm – 39cm37cm – 42cm40cm – 45cm43cm – 48cm45cm – 50cm
Arm sleeves bicep size (all)26cm – 31cm29cm – 34cm32cm – 37cm35cm – 40cm38cm – 43cm42cm – 46cm

Glove sizes

SizeXSSMLXL
Gloves17cm17.5cm18cm18.5cm19cm
Gloves (when worn as a liner)17.5cm18cm18.5cm19cm20cm

Women's sizes

SizeXSSMLXL
Tops (chest, UK)810121416
Leggings & shorts (waist, UK)810121416
Tops (chest, USA)4681012
Leggings & shorts (waist, USA)4681012
Tops (chest, EU)3638404244
Leggings & shorts (waist, EU)3638404244

Men's sizes

SizeXSSMLXL2XL
Tops (chest)34" – 36"36" – 38"38" – 40"40" – 42"42" – 44"46" – 48"
Leggings & shorts (waist)28"30"32"34"36"38"
Leggings & shorts (inner leg)27" – 28"28" – 30"30" – 32"34"34"34"
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Frequently asked questions

Is my order tracked?

Absolutely. As soon as your vest leaves the warehouse, you will receive a shipping confirmation email containing a direct tracking link. You can follow your package's journey every step of the way right to your front door.

How much is shipping and how long does it take?

We offer simple shipping options for all mainland UK orders:

• Running Vests:

  • Standard Shipping (3–4 Calendar Days): FREE
  • Expedited Shipping (1–2 Calendar Days): £4.99

• Enertor Insoles:

  • Standard Shipping (3–4 Calendar Days): FREE
  • Expedited Shipping (1–2 Calendar Days): £5.04

• Socks (Partner Fulfilled):

  • Standard Shipping (3–5 Working Days): £2.99
  • Express Shipping (Tracked: 2–3 Working Days): £4.99

Order Processing & Cut-Off Times
• Cut-Off Time: Orders placed before 2:00 PM GMT are processed the same day. Orders placed after, or on UK Bank Holidays, will be processed the following day.
• 7-Day Delivery: Once dispatched, deliveries take place seven days a week, including Saturdays and Sundays. Please note that couriers do not deliver on official UK Bank Holidays, and these orders will arrive the next available day.

How Your Order is Fulfilled
To get your gear to you as fast and reliably as possible, we store our dedicated UK inventory within a premium professional fulfillment network managed by Amazon. Your running vests and insoles will arrive in high-quality, plain packaging to protect your unboxing experience. However, please don't be surprised if your tracking details or delivery courier are from Amazon Logistics—we use their world-class logistics to ensure your order hits your doorstep efficiently. Sock orders are fulfilled and dispatched directly by a partner brand.

What is the return policy?

Our goal is for every customer to be totally satisfied with their purchase. If this isn't the case, let us know and we'll do our best to work with you to make it right. You have 30 days from purchase to return a product due to an incorrect size ordered or to report a defect.

I want to ask a question...

Head to our contact page here, fill in the form and we'll get back to you within 24 hours.

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