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Specifications

Collection Summer 2026
Color specification Black
Condition New model
Gender Men
Season Autumn, Winter
View all specifications

Description

The Assos thermobooster undershirt p1 is a versatile, packable undershirt.

The ultra-breathable thermal layer for intense rides has now been updated with pockets, allowing it to be used as a jersey in cool conditions or as a midlayer for extra protection in the coldest, most challenging conditions.

BEHIND THE PRODUCT
The new thermal fabric is a highly elastic warp-knit that wraps aerodynamically around the contours of your body. It's also breathable enough for intense efforts, and if the temperature or effort becomes too high, the ThermoBooster P1 can be folded down to the size of a rain jacket and stored in a rear pocket of your jersey. The versatile fabric and second-skin fit make it suitable for multiple seasons—wear it over a base layer or summer jersey in spring and fall, and use it as a midlayer under a stormproof jacket for extra thermoregulation in the harsh winter.

WHEN/HOW TO USE
For cool conditions, combine the ThermoBooster P1 with a base layer and a summer set or the EQUIPE R Spring Fall Bib Shorts. In harsh winter conditions, use it as a midlayer in your winter 3/3 layering system.

REFINED DETAILS:
HIGHLIGHTED FABRICS
Skuba is a new fabric with a circular knit structure and a soft, carbon-brushed interior that creates a layer of volume for heat insulation. It is also breathable enough to maintain a dry microclimate during intense efforts. CONSTRUCTION/FIT Our AEPD 11 racingFit is a second-skin, aerodynamic silhouette, designed with feedback.

Select Size What is my size?
RRP 199,95

168,95

You save 31,-

Delivery within 2 – 4 business days

Customers rate Triathlongear24 4.5/5
60-day return period
Free delivery from €50,-
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Personal advice from our specialists

Do you have a question about this product, sizing, the material, or anything else? Our specialists are happy to help.

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Fitting in Volkel, with personal advice

Would you like to see or try on this product first? Then visit our store in Volkel (Brabantstraat 16, 5408 PS, North Brabant), The Netherlands.

Tip: please check in advance (by phone +31(0)413-256800, or via [email protected]) whether this product is in stock in our store.

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Questions about delivery, delivery times or returns? We’ve listed everything clearly for you.

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Curious how this wetsuit feels in the water? Come test it during our wetsuit test days. See all dates and info via wetsuit test days.

Tip: check in advance whether this product will also be available during the wetsuit test days.

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Specifications

Collection Summer 2026
Color specification Black
Condition New model
Gender Men
Season Autumn, Winter
Size S
Supplier item number 11.24.388.18/S
Warranty 2 years

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