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Castelli Mens Core Seamless Baselayer White
Castelli Mens Core Seamless Baselayer Castelli Men
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Castelli Mens Core Seamless Baselayer 1
Castelli Mens Core Seamless Baselayer 2

Castelli Men's Core Seamless Baselayer

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Mfg PartNum:
MSRP: $74.99
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The Core Layer — Soft and Stretchy

Seamless construction paired with a sleeveless cut, promises stretch and comfort with less bulk. The Castelli Men's Core Seamless Baselayer is the next-to-skin layer for those rides that are not too hot and not too cold. Just right.

Most base layers on the market have nylon and Lycra® mix that feels comfortable when you put it on but then ends up feeling wet when you're riding, and you freeze when you stop. The Core is different.

Castelli has worked hard to make this Core Seamless base layer keep you comfortable and dry, thanks to the addition of polypropylene and polyester yarns, while not compromising the stretch comfort of seamless. Seamless for comfort and surprisingly warm for its weight, this base layer also provides a mild level of insulation with a high level of breathability. A wide neck opening is perfect for fitting under short-collared jerseys, keeping your neckline clear and comfortable.


  • Lightweight
  • Seamless construction means extra comfort
  • Composed of 84% polyester and 16% polypropylene yarns
  • Wide neck opening to fit under short-collared jerseys
  • Ideal for shoulder season riding — Spring and Fall
  • Performance fit: Castelli apparel is designed with a performance cut that often runs smaller than that of other manufacturers. Consider sizing-up one size to ensure a comfortable fit — e.g., if you typically wear a Medium, select a Large in Castelli.

    Feel free to contact us with any questions or concerns.

  • B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.

    The product weight specified is an approximate weight based on the manufacturer's specifications (if available) or our measurement of one or two examples. For most products, the weight will typically vary by 5% to 10%.

    Size Chart



    Sleeve Type: Sleeveless 

    Fit: Form Fit 

    Season: Spring Summer Fall 

    Weight: ~45 g

    Fabric: synthetic 

    White - S/M

    Mfg PartNum: A20031001-2 

    White - L/XL

    Mfg PartNum: A20031001-4 

    White - 2X-Large

    Mfg PartNum: A20031001-6 

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