Free 2-Day Shipping on Orders Over $50*

Detail Images

  • Castelli - Back
  • Castelli - Flanders Warm Base Layer - Long-Sleeve - Men's - Grey
  • Castelli - Back -

Current Color

  • Castelli - Flanders Warm Base Layer - Long-Sleeve - Men's - Grey

Castelli Flanders Warm Base Layer - Long-Sleeve - Men's

sale $59.96 $79.9525% Off

Free 2-Day shipping on orders over $50*

Select a Size:

Select options
  • Select options
    • S
    • M
    • L
    • XL
    • XXL

    Select a Color:

    Select options
  • Select options
    • Grey

    10 Reviews


    Soft layering for hard conditions.

    Nothing ruins a ride faster than catching a chill. Except maybe a flat tire. Or slushy conditions. Well OK, there are lots of things that rival catching a chill, but we still don't like it. So as the seasons change, we start thinking along the lines of layers, and this inevitably leads us to the Castelli Flanders Warm Base Layer.

    The Flanders is made with a durable SottoZero Fleece that insulates and wicks. Dryer, after all, is warmer. Mesh inserts provide ventilation in the underarms, just in case you overheat, and the flatlock stitching and flat hems mean the Flanders will fit comfortably as a piece of layering gear. Castelli recommends it for use in 23 to 46 degrees Fahrenheit, and, while this range may seem excessive, we find that the Flanders gets the job done in all conditions when layered with the right outer layer.

    The Castelli Flanders Warm Base Layer - Men's is available in six sizes ranging from X-Small to XX-Large in the color Grey.

    • Item #CST002W

    Tech Specs

    Manufacturer Warranty
    1 year
    Recommended Use
    cold-weather cycling
    Claimed Weight
    116 g
    SottoZero Fleece

    Tech Specs

    • Reviews
    • Q & A

    What do you think about this product?

    Have questions about this product?

    Warmest base I own

    • Familiarity: I've put it through the wringer
    • Fit: True to size
    • Size Bought: Medium

    I've now ridden probably 5-6 rides in a New York winter in this base and am very impressed. Super-warm (almost too much so!) and fits perfectly. The fleece backing makes this feel almost like a thick jersey on its own. In 30-40F temps I'll wear this under a soft-shell jacket or heavy-weight winter jersey and be verging on overdressed once I've warmed up. Note that the thick material doesn't dry nearly as quickly as lighter synthetic or merino base layers - when I've gotten sweaty in the early part of a ride I've stayed that way for a while.

    Generally very happy and this has become my go-to for deep winter.

    Great Great Base Layer

    • Familiarity: I've used it several times
    • Fit: Runs small

    While chatting with Zach on the chat line, he recommended this Castelli base layer. When you first take it out of the box you wonder how such a thin garment could be warm. It is. Really warm. I was warm with just this and a long sleeve jersey in 40 degree weather. This is an amazing shirt. It feels like a man-made wool only softer and without any itch. I'm between a S and M in size on Castelli products and Zach recommended a M. He was right and the M is still snug but not tight. After one use I bought another one. I love it.

    Perfect winter base layer

    • Familiarity: I've put it through the wringer
    • Fit: True to size
    • Size Bought: Large

    Very thin and light, but works incredibly well. My go-to setup for winter riding. On extra cold days, wearing a mesh summer layer underneath is a neat trick. This creates and extra layer of air pockets and improves the insulation considerably. I have washed it at least 20 times at this point and it's kept up really well. No tearing or piling of the soft inner layer at all.

    My go to deep winter base layer.

    • Familiarity: I've used it several times
    • Fit: Runs small

    I was looking for a thin but warmer base layer for colder temps here in the South. I have a Craft Extreme base layer but it is just not quite enough. I wanted to find a base layer to wear under my wet/winter jacket, the Giordana FormaRed Carbon jacket. This fits the bill great. Went for a ride saturday with starting temp 31F, chill factor 21F, and 13 mph wind. Wore just this under the jacket and it worked great. Was plenty warm and has sweated in it a good bit but it never felt wet nor did I feel chilly. For reference I had on Giordana G-Shield long thermal bib tights which rock in cold and rainy winter weather. I bought a XXL knowing the typical buy one size up which works for most Castelli purchases. I am 6 feet and 215 pounds. I wrote this review after two rides because it only took one ride to know this was the solution.

    This thing straight up rocks!

    • Familiarity: I've used it once or twice and have initial impressions
    • Fit: True to size
    • Size Bought: XL

    Used this the other day as a base layer, with a SmartWool Microfleece over it, and a couple other layers over that. After riding about four hours in 40 degree temps, I still felt warm and as dry as I think is possible while cycling. When I took off all my layers, everything was a bit damp, but the Castelli was pretty much bone dry. So far, only thing to do that for me, so it is definitely a keeper.

    I am 6'0 tall, weigh 165 lbs., and my arms are maybe a bit longer than average. The Castelli fit perfectly, snug but not confining, a little longer than my waistline in the back, and just long enough at the arms. I would have liked another inch at the wrists, but they don't creep up, they stay where they are, so that's good.

    The fit at the neck was snug, but not tight at all. Extremely comfortable, amazing quality. I originally bought the 1/4 zip, but all my other layers have zips, so I ordered the crew neck to replace it.

    After wearing it, I decided to keep the 1/4 zip version as well, figured I would use it when the temps are in the 60's when I don't have so many layers over it.

    Highly recommended, best base layer I have found so far.

    How on Earth did they manage it?

    • Familiarity: I've used it several times

    This base layer is thin and lightweight. So thin you can see right through it. But it's warmer on a 30 degree day than a Pearl Izumi base layer I own that is at least 3 times as thick, and weighs more than twice as much!

    Great product

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

    Like other Castelli baselayers, this seems like some thin fabric and you wonder if it's really going to work. Despite its light weight, this is a fantastic base layer. I just got back from a 2.5 hour ride at 31 F and it was perfect. Not too hot or cold, and not wet. As for sizing, it runs true to Castelli sizing. I'm 5' 6", 40" chest, 155 lbs, and normally wear a large in Castelli. A large in this is a perfect fit.