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Newton Arm Warmers

Fabric Guide Size Guide

Accessories Size Chart


All sizes are given in US Sizing 

Men's Women's
S 4 - 6 5.5 - 7.5
7 - 9 8.5 - 10.5
L 10 - 12 11.5 - 13.5
XL 13  14+

Arm warmers

Measurement given for bicep width. Measure around the fullest part of your upper arm in a relaxed position. 

Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit.

Approximate measurements only. 

XS / S 23 - 28 cm
S / M  29 - 33 cm
M / L 34 cm +


Hand Length - Measure from the top of your middle finger to the base of your hand. 

Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit.

Chaser Gloves:

S/M 16.5 cm
L/XL  18.5 cm 

Newton Gloves:

S 16.5 cm
18.5 cm 
L 20.5 cm

Skull Cap

To measure your head circumference, take a sewing measuring tape and wrap around your head so that the measuring tape winds just above the ears, in the middle of your forehead and in the centre back of your head.

Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit. Approximate measurements only.

Head circumference
S/M 50-60 cm
M/L  60-70 cm 

For further assistance with sizing, contact us here.

or make 4 interest-free payments of $13.75 fortnightly with More info


Made from our revolutionary, new, Merino Wool compression fabric, the Arm Warmers are ideal for changing weather conditions and trans-seasonal weather. They maximise heat retention and offer additional coverage in low temperatures, but are easily removed or rolled down if it warms up or if you're wearing a pack.

Unlike regular arm sleeve, this fabric has a high merino content so are fully breathable, lightweight, and deliver both UV protection from the sun and warmth without bulk, and help stop you overheating. Pair with a t-shirt to add some additional warmth and versatility to your favourite short sleeve ioMerino.

Tag-free labels and flatlock stitching eliminate chafe and maximize comfort. Silicone grippers at the inside top hem to hold them securely in place around your arm and the reflective trims add visibility in low light conditions.

Model is 6'2" and wears size M/L. 

Female model wear size XS/S. Model is size 6-8, height 170cm, chest 81cm, waist 63.5cm, hips 89cm

Choose size based on what base layer top size you wear. 

Size Guide. Contact Fit.



Midweight 280gsm 

76% superfine Australian Merino Wool

15% Elastane for compression, lift and support

9% Nylon for added durability



Customer Reviews

Based on 34 reviews
Sonja Jansen (Adelaide CBD, AU)

These seem warmers are warm, comfortable, fit well and stay up. I used them one morning when the frosts didn't warm up for three hours and I was comfortable.

Nicolas Rasmussen (Sydney, AU)
Top notch

These are softer and more breathable, and better in cold than my old merino blend warmers from DHB. I have long arms for my height but the S/M are still long enough and not too loose. Silicone grip band is strong so no slipping, and no discomfort up to 3h. Recommended.

Nikki R.

These arm warmers are perfect for rain, wind and changeable weather conditions. The fit is perfect. They stay put and are easy to put on and off. I wore them with an iomerino t shirt and the combination was super comfortable. I’m so impressed with this fabric that I would like to try the long compression tights. Great brand. Fantastic for the wool industry.

Karen Buchegger
Gets me through winter

I love these arm warmers, they keep me warm without the bulk. I wear them all through winter.

Melissa (Adelaide, AU)

Saved my day. Cold start to my half marathon recently and the arm warmers (along with my io merino tshirt) made a huge difference.

Stayed in place well and rolled up small to stuff in pockets later.

Cons. Snug fitting sleeve. Take this into account when ordering.

Alistair Reid (Minden, AU)

delivery was really quick and product was high quality - worked really well at freezing temps over many hours of an ultra


Fabric Guide

While Merino is an amazing natural fibre, not all Merino fabrics are created equal. At ioMerino, we make our own fabrics, using only the best quality fibres, and to very specific specifications that make the most of the natural benefits of Merino. All of them are 'Merino rich’. No cheap blends passed off as Merino. No cheaper scratchy fibres or synthetic substitutes to save money. No unethical production. And each fabric is made for a specific purpose. So if you see something with a small amount of elastase or nylon added, you can be sure it absolutely needs to be there to enhance the natural stretch and durability. 

It took every bit of our 140 years of experience in the wool industry to perfect our fabrics, but we think you’ll agree the end result was more than worth the effort.

Ethically Made. Ethically Sourced. Perfectly Natural. 


Altitude / Zodiac

Lightweight 170gsm 96% Australian Merino Wool with 4% elastane for extra stretch and comfort. A MicroMerino® Fabric. 


Ultra / Universal

Lightweight 160gsm 83% Australian Merino Wool blended with 12% nylon blended for extra durability and 5% Elastane for stretch and comfort.



Midweight 265gsm 96% Australian Merino Wool with 4% elastane for extra stretch and comfort. A MicroMerino® Fabric. 


Summerino - Celsius 

Made from 45% ultra fine MERINO (Ultra Lightweight 150gsm), 45% natural TENCEL (made from sustainably grown wood fiber), and 10% nylon for extra durability. 


Summerino - Keystone 

Ultra Lightweight 150gsm 100% Australian Merino Wool. A MicroMerino® Fabric. 


Merino Compression

Midweight 280gsm 76% Australian Merino Wool, 15% Elastane and 9% Nylon for extra stretch and compression properties.



Ultra lightweight ribbed 155gsm 100% Australian Merino Wool. A MicroMerino®  Fabric. 



Outer Weight 280gsm Fleece 100% Australian Merino Wool. MicroMerino®  Fabric. 



Midweight 260gsm 100% Australian Merino Wool. A MicroMerino®  Fabric. 



Midweight 260gsm waffle texture 100% Australian Merino Wool. A MicroMerino®  Fabric. 


Stride / Glacier / Velocity

Midweight 255gsm French Terry 100% Australian Merino Wool. A MicroMerino®  Fabric. 


Natural Merino Wool benefits: