Castelli Core Seamless Base Layer SS - White
Apparel
Castelli Core Seamless Base Layer SS - White
Castelli Core Seamless Base Layer SS - White
The Castelli Core Seamless Base Layer SS in White is the warm-weather short-sleeve foundation layer that works under any summer or spring jersey without showing through as a dark underlayer. Read the overview
1 in stock
- Free shipping on orders over $100. US addresses only.
- 30-day returns in new condition. Read the return policy.
- Price matching. Found it for less? See how it works.
Overview
What Does the Castelli Core Seamless Base Layer SS in White Do for Your Ride?
The Castelli Core Seamless Base Layer SS in White is the warm-weather short-sleeve foundation layer that works under any summer or spring jersey without showing through as a dark underlayer. Seamless construction removes the shoulder and underarm seams that generate friction over long hours on the bike in an aggressive position, and the snug body-mapped fit stays flat against the skin without creating visible bulk at the collar or waistline. White is the practical choice when riding in white or light-colored jerseys where a black or colored base layer shows through uncomfortably.
The moisture-wicking fabric pulls sweat away from the skin and allows the jersey above to function as intended by keeping the base layer from saturating against your skin. The flat waistband stays tucked into bibs cleanly without rolling or bunching, and the slim cut avoids adding a stacked layer of fabric under your jersey on hot days. Machine washable in sizes XS through XL, made in Italy, the Core Seamless SS in White is the base layer that stays hidden so your kit can do its job.
All the specs
- Construction
- Seamless body-mapped knit
- Sleeve
- Short sleeve
- Fabric
- Moisture-wicking
- Colorway
- White
- Sizing
- XS, S, M, L, XL
- Care
- Machine washable
- Origin
- Made in Italy
Good questions
Get to know Castelli
There's more to Castelli than this one product. Our Castelli page has the full Castelli lineup we carry and more about the brand.
Visit the Castelli page →Why choose White over Black for a base layer?
White is the right choice under light-colored or white jerseys where a black base layer shows through visibly. In hot summer sun, white also absorbs less radiant heat than dark colors, which can keep you marginally cooler.
Does a short-sleeve base layer actually help in hot conditions?
Yes. A base layer wicks sweat away from the skin faster than skin-to-jersey contact alone, which improves evaporative cooling. The seamless construction also ensures the layer stays off your skin's surface rather than clinging flat.
Does the White stay opaque when wet with sweat?
The white colorway may become slightly more transparent when saturated with sweat. This is normal for any white technical fabric. The jersey worn over it minimizes any visibility concern.
What riders say about the Lab
“Paul does a great job. He got my bike I bought from someone there in their town and had it packed and shipped to me in Austin, TX… It got here in perfect condition!”
“Fantastic store. It has everything you may want/need for cycling. Great team. Highly recommend to anyone looking for cycling related things and bike service.”
“I recently got back into biking and wanted to add some things onto my bike. They had most of what I was looking for in shop… I'm really happy to have found them.”
Questions about this one?
Not sure on size, fit, or whether this is the right one for you? Ask us. A real person here will answer.
Goes straight to the Lab with the product you were looking at attached. No newsletter signup.
