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Castelli Thermoflex Classic Knee Warmer

Sale $31.96 $39.95 20% off

Item # CST0106

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  • Black, XL ($31.96)
  • Red, S ($31.96)
  • Red, M ($31.96)
  • Red, L ($31.96)
  • Red, XL ($31.96)
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Item # CST0106

Extend the temperature range of your biking shorts with Castelli's Thermoflex Knee Warmers.

If you ever wish your bike shorts could magically grow to cover your knees when it gets cold, or that your pants could shrink up for spring riding, grab the Castelli Thermoflex Knee Warmers. These stretchy fleece warmers cover your knees, so you can pair them with your riding shorts on chilly days. Elastic on the cuffs of the Thermoflex Knee Warmers gives them a solid fit, while Castelli's scorpion logo adds eye-catching detail.

  • Stretch synthetic
  • Moisture-wicking
  • Fleece lined

Tech Specs

stretch synthetic, fleece lining
Recommended Use:
Manufacturer Warranty:
30 days

Community & Reviews

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Castelli Thermoflex Classic Knee Warmer

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Here's what others have to say...

4 5

Great product

  • Familiarity: I've used it once or twice and have initial impressions

Great feel and warmth,just the wrong size (XL). Will exchange for L.

I'm 6'2 168lb with pretty dang skinny legs. What size do you suggest? I'm guessing medium but I typically size up in castelli... Thoughts?

Responded on

Greetings - would go with a Large - as your inseam will most likely need the extra length ;)

4 5

nothing fancy but get the job done

  • Familiarity: I've put it through the wringer

I bought these a year ago. they have a simple design but the brushed fleece is comfortable and adds to warmth. I use them in temps from the mid-40s to 60. 5'8" 145lbs and purchased size medium

5 5

Sizing question.

I am 6'2" 210 lbs. any suggestions on size? Thanks.

Responded on

I'm 6'0" and the Large fits well. It goes to mid-calf. I guess I have normal sized legs and they are not too tight or loose.

Avg. ride time: 10h 43m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.
5 5

Oh so cozy

Love these for those crisp morning rides where leg warmers would just be too much, but flying bare would be too uncomfortably chilly. These are made of a quality and cozy material, and come at a surprisingly low price for Castelli. I am 5'10 160lbs and found the medium to fit perfectly.

Avg. ride time: 6h 6m per week
  • Average ride time is based on Strava activity over the last 3 months. Give your reviews credibility by connecting your account.

What size do I need? I am 5'10 150 ibs

What size do I need? I am 5'10 150 ibs

Best Answer Responded on

Medium should fit you spot on :)

5 5

Excellent and great value

These are really great knee warmers. Good fit and looks, very comfortable. At this price, they're a steal. I highly recommend these.

fall riding

Responded on

Fun video, but not specifically useful for evaluating these knee warmers.

my husband had knee surgery and the cold...

my husband had knee surgery and the cold really gets to his knees. Will these help or are they just for bile riders

Responded on

They should work for anyone that needs to keep their Knees warm. He may have problems with them falling down because of no Lycra short holding them up.

5 5


These are perfect for cold weather rides. I don't own a pair of full length bibs, but these are warm enough for rides between 40 - 50 degree f.