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Castelli Estremo Shoe Covers


The Castelli Estremo Shoe Covers are built for extremely cold conditions – keeping your toasty well below freezing, the Estremo is fully windproof and keeps water away whilst retaining breathability... Read more

SKU: CS195250102


The Castelli Estremo Shoe Covers are built for extremely cold conditions – keeping your toasty well below freezing, the Estremo is fully windproof and keeps water away whilst retaining breathability.

The Estremo is Castelli’s warmest shoe cover produced to date, owing to its innovative composition that has been explicitly selected to keep you insulated on cold-weather adventures.

All-new and updated Gore-Tex Infinium fabric offers unrivalled, high-grade water protection, keeping you dry when you encounter those inevitable rainy showers and crucially gives you full windproof protection. Despite its protective properties, Gore-Tex Infinium is also breathable meaning that your feet remain at an optimal temperature, even when the temperature fluctuates.

The fleece-backing of the Gore-Tex Infinium is met with an additional fleece-layer of Polartec material which has a thick loft to trap air close to the skin whilst contributing to moisture management.

A specialised construction around the ball of the foot means that although the Estremo is thick, rub on your crank arm when worn is minimised. The YKK AquaGuard zipper is primed to protect you from additional spray whilst the extra overall height gives even more foul-weather protection. These careful considerations reflect Castelli’s ongoing commitment to creating fully ride-ready performance garments and make the Estremo shoe covers a must-have for cold climes expeditions or midwinter training.

Key Features
  • Extreme condition cold-weather shoe cover
  • Gore-Tex Infinium fabric breathable, windproof and water-resistant
  • Polartec PowerStretch Pro fleece lining for extra warmth
  • Reflective details for low-light visibility
  • YKK AquaGuard Zipper
  • Highly durable underfoot material
  • Suited for -10˚C to -5˚C

ABOUT Castelli

Castelli Cycling is the most innovative, stylish and prestigious cycling clothier in the world. Decades of pro cycling development and a passion for perfection in materials, cut and performance has seen the brand reinvent cycle wear time after time. From the first Lycra shorts to sublimated printing, the game-changing Gabba and aerodynamic apparel, Castelli continues to set a path that others can only follow while maintaining generations of Italian heritage. Read more about Castelli.


Founded by real cycling enthusiasts in 2004, our passion for elite performance runs through everything we do at Saddleback. Our team of dedicated roadies, mountain bikers and triathletes practice what we preach to bring you the finest cycling products and a superior service to match. We're the official UK home of Castelli, Chris King, ENVE, HJC, Moots Cycles, PUSH, Sidi, Silca, Sportful, Stages, Troy Lee Designs and Wolf Tooth.


Castelli Overshoes Size Guide


F - Men's EU Shoe Size - 36-39 40-42 43-44 45-46 46-48
F - Women's EU Shoe Size 35-37 37-39 39-42 - - -

Castelli shoe covers are designed around an EU shoe size that will fit snugly over a sleek road racing shoe of the corresponding size. If your road shoes are bulky, wider than traditionally narrow Italian shoes such as Sidi, or shoes that feature adjustable heels or dial-style closures then consider sizing up.

If you have a side dial-style closure we don't recommend a side zippered shoe cover, instead choose a design with choose a rearward zipper.

If your shoes are designed for touring, commuting or mountain biking please select an All-Road shoe cover as Castelli's standard shoe covers will not fit this style of shoe.

Shoe Covers (unisex)

F - Euro Shoe Size 36-40 40-44 44-48

Multi-size Castelli shoe covers will fit snuggly on most shoes in the suggested range. However, please consider sizing up if your shoes are wider than standard or have large exterior dial-style buckles or if you are towards the top end of a size on the guide above.

So for example if you have a wide fitting shoe with external buckles and are size 44, consider a 2XL cover rather than squeezing into a L/XL cover.

As with Castelli overshoes, If you have a side dial-style closure we don't recommend a side zippered shoe cover, instead choose a design with choose a rearward zipper.

If your shoes are designed for touring, commuting or mountain biking please select an All-Road shoe cover as Castelli's standard shoe covers will not fit this style of shoe.


Castelli Warmers Size Guide

Jersey/Short Size Your Weight Suggested Warmer Size
XS-S 45-60KG S (WOMAN)
S-M 45-60KG S (MAN)
S-M 60-70KG M
L-XL 70-80KG L
2XL-3XL >80KG XL

Castelli warmer sizing relates to your jersey or short size and your body weight.

Warmers have a lot of stretch and for designs incorporating Thermoflex fabric, you can size down.

However, we would not recommend sizing down for Nano Flex and Nano Flex Plus products.


Castelli Casualwear Size Guide

CHEST - CM 88 92 96 100 105 110 115
WAIST - CM 76 80 84 88 93 98 103
HIPS - CM 90 94 98 102 107 112 117
INSEAM - CM 81 82 83 84 85 86 87
CHEST - CM 79 84 89 94 99
WAIST - CM 63 68 73 78 83
HIPS - CM 87 92 97 102 107
INSEAM - CM 75 76 77 78 79

Castelli casual clothing is designed to give a loose fit when correlated to your jersey size. So if you wear a Gabba in L, you will achieve a casual loose fit with a L-sized T-shirt. Bearing this in mind, if you prefer a closer fit you may wish to size down.

For shorts and trousers, please select the same size as you would for bibshorts or tights. Women's T-shits and hoodies are designed for the female form. All other casual pieces are designed to be suitable for both men and women.


Castelli Bras Size Guide

G Under Bust Measurement in CM 68-72 73-77 78-82 83-87 88-89
Light Bra A & B Cup Sizes XS S M L XL
Support Bra C & D Cup Sizes XS S M L XL

The Light Bra is designed for A and B cup sizes only. The Bellissimo bra is designed for B and C cup sizes only. The Support Bra is designed for C and D cup sizes only.

Please note these are cycling bras and are designed to offer light support and maximum breathability on a bike. They should not replace a sports bra for high impact sports.

To determine your frame size measure under the bust as indicated. To calculate your cup size measure around the fullest part of the bust. If the difference is less than 15cm, you will require the Light Bra. If the difference is greater than 15cm but less than 20cm, we recommend the support Bra. If the difference is greater than 20cm we would recommend you buy a commercially available sports bra.


CHPT3 Size Guide

CHPT3 – Tailored Sizing (pre-2020)

Chest Inch CM Waist Inch CM
A - 36 36 91.5 B - 29  29 73.5 
A - 38 38 96.5 B - 30  30  76
A - 39 39 99 B - 31  31  78.5
A - 40 40 101.5 B - 32   32  81
A - 41 41 104 B - 33  33  83.5
A - 42 42 106.5 B - 34  34 86 
A - 44 44 111.5 B - 36  36  91

CHPT3 clothing uses a tailoring system for its sizes. The physical chest or waist size is used as the garment size. If you have a 40" chest, you will need a 40" jersey. Please note that while the CHPT3 range is not designed for racing, it is still a close fitting athletic design suitable for active cyclists.

CHPT3 - 2020 range onwards

A - Chest B - Waist C - Hips D - Inseam
XS 88cm 76cm 90cm 81cm
S 92cm 80cm 94cm 82cm
M 96cm 84cm 98cm 83cm
L 100cm 88cm 102cm 84cm
XL 105cm 93cm 107cm 85cm
2XL 110cm 98cm 112cm 86cm
3XL 115cm 104cm 116cm 87cm

Men's and unisex Castelli sizing is based on your physical measurements and the garment's intended use. Race items are designed to use fabric stretch to achieve a very snug fit; as such physical garment sizes vary within the range. Please don't compare sizing with other manufactures. The sizes shown above are for the maximum size, so someone with a 99cm chest would be a size L. If you have a 101cm chest then you're an XL.


Sidi Cycling Shoes Size Guide

Sidi EU Size UK Size US Size Length (cm)
35 13 1 23
35.5 13 1 23
36 1 2 23.5
36.5 1 2 23.5
37 2 3 24
37.5 2 3 24
38 3 4 24.5
38.5 3 4 24.5
39 4 5 25
39.5 4 5 25
40 5 6 25.5
40.5 5 6 25.5
41 6 7 26
41.5 6 7 26
42 7 8 26.5
42.5 7 8 26.5
43 8 9 27
43.5 8 9 27
44 9 10 27.5
44.5 9 10 27.5
45 10 11 28
45.5 10 11 28
46 11 12 28.5
46.5 11 12 28.5
47 12 13 29
47.5 12 13 29
48 13 14 29.5

Sidi fitting guide

Like many handcrafted Italian shoes, Sidi cycling shoes feature a slim fit, the equivalent of a ‘D’ width. In our experience, if you’re usually a 45 in cycling shoes, you’ll be a 45 in Sidi shoes.

However, you also have the option of Sidi’s half sizes. These use the same length soles as the main size (i.e. 45 and 45.5 are the same length) but use a larger volume upper. This is perfect if you need a touch more width, have slightly higher arches or use an insole that takes up some of the volume of your shoe.

The volume and fit of the shoe is also affected by the closure system utilised. We’ve found that the combination of a central dial with the Soft Instep 4 strap means the Sidi Wire 2 has a slightly roomier toebox than the rest of the range, making it ideal for those seeking Italian styling with a little extra wiggle room.

If you need more volume, Sidi’s range of Mega fit shoes feature soles that are 4mm wider and have larger uppers for those with higher volume feet or deep orthotics.

Of course, everyone’s feet are different and slipping the shoes on will give you the best idea. We’d recommend trying them on towards the end of the day or even after a long ride to give your feet a chance to swell to their maximum size.

If your toes are brushing the end of the shoe, they’re too small. If you stand on tiptoes and the heel of the shoe doesn’t lift with the heel of your foot, creating a gap, they’re too big.


TLD D3/D4 Helmet Size Guide


TLD A1/A2 Helmet Size Guide


Sportful Clothing Size Guide


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