On Monday, Castelli introduced the latest version of its cold-weather shell, the Perfetto RoS 3, built from a new fabric called Polartec AirCore. The material is exclusive to Castelli and Sportful in the cycling industry until 2026.
AirCore was developed with Polartec using recycled polyester yarns and is free of PFAS-based (per- and polyfluoroalkyl substances) chemicals. The membrane is produced by electrospinning, a process that creates a tight but permeable barrier by pushing polymer filaments through a charged needle. The result is a fabric that blocks wind and rain while still allowing a controlled amount of air to move through it.
Testing has shown that the material allows air in, compared to most cycling membranes that block air completely. Its hydrostatic rating of 5,000 mm means it is waterproof in practice, even if it doesn’t meet the stricter 10,000 mm definition. The aim is to balance water resistance with enough ventilation to prevent sweat from building up inside the jacket.
The Perfetto RoS 3 is designed for riding in temperatures from 4 to 14 C. Both men’s and women’s versions include taped shoulder seams and side zippers for extra ventilation. There is also a high collar, long tail, three rear pockets with drain holes and reflective details.
The men’s colours include red, light black, mocha and blue, while the women’s options include hibiscus, pool blue, mango and light black.
Castelli Perfetto RoS 3 jacket, $400.00