RRP £60-70

Not merely a natty pattern printed onto an existing Castelli base layer. The Chpt.3 1.83 sleeveless base layer had its genesis years ago in the Tour de France and has only now been realised.

The fabric is a microfiber polyester made as light and soft as possible. Its hydrophilic outer layer wicks moisture off the skin to the jersey yet, unlike hydrophobic materials, doesn’t absorb moisture along the way. It is designed so that when paired with the 1.21 Jersey you end up with the combined weight of a normal looking jersey only with much better comfort and moisture management.

In contrast to the subdued colours of the outer layers, the Chpt.3 base layer is a bit more colourful, much the way a gentleman may choose the inner lining of his suit to contrast with the outside. In tailoring this is called a reveal, a flash of colour occasionally glimpsed that shows there’s something more going on than at first perceived. The neck is a little more round than normal, compensating for the higher necks of the 1.21 and 1.61. You'll note that the base layers are only available in a sleeveless cut, this is because the base is designed to be used with the 1.21 Jersey and sleeves on an undershirt can often be more uncomfortable with a short sleeve jersey.

The fabric in the Base Layer 1.81 was originally used to make a super lightweight climber’s jersey for the Tour de France, Fabian Wegmann (a Garmin and Castelli racer on that year’s Tour de France) mentioned to Castelli he thought it would make an excellent base layer material – this is the first time that idea has become a reality. It is very lightweight and has superb wicking properties, exactly what is required of a lightweight climber’s jersey AND also a base layer.

What was learnt while using it as a climbing jersey at the Tour de France was that it didn’t have very high longevity because of unstitching at the hems – and this was due to the very fact the fabric was so lightweight it couldn’t hold the stitching adequately. The solution to this has been to create ‘false’ hems, instead of folding over the edge of the material and sewing it down there are additional panels of material sewn on with double stitching where the fold of the hem would normally be.

In addition there are two panels of more flexible fabric added into the hip area to increase comfort and mobility while in the cycling position.

After 18 years as a professional with over a thousand days racing under his belt, there was one day’s racing Millar had never completed: Paris-Roubaix. In his final year, 2014, it was one of Millar's primary objectives to finish the 257km, 28 cobbled sections totalling nearly 60km, and two laps of a velodrome.

Standing in the middle of that most famous of velodromes, helmet off, knocking back a Fanta, face covered in dirt, feeling a bit of a hero, Millar's wife told him he had one more lap to do. ONEMORELAP? Getting back on his bike, he completed the race. When it came to finding inspiration for new interpretation of the Chpt.3 classic base layer there was only one classic worth representing, the queen of them all.

The ONEMORELAP Sleeveless Base Layer uses the same build as the much loved original Vuelta themed 1.81 Base Layer, but Chpt3 designer Richard Pearce created this unique perspective on the finish line of that most famous velodrome. The ONEMORELAP Sleeveless Base Layer serves as a reminder to us all that sometimes finishing can be as important as winning.

The 1.83 Base Layer utilises the pattern from the ONEMORELAP series of products using the ‘Finish Line’ Graphic of the Roubaix Velodrome.

Lightweight 3D mesh fabric is 100% microfibre polyester for minimal moisture absorption

Hydrophilic outer layer

Neck, arm holes and hem are lined for additional comfort

Stretch panels at hem

Woven label

Weight: 68g