Alpinestars Stella SMX Air Women's Jacket The Alpinestars Stella SMX Air Women's Jacket is a tech mesh jacket with 450D polyfabric reinforcement in key areas. An ergonomic design provides optimal sport movement with extreme flexibility. DFS lite external shoulder protectors combine with CE Level 1 Alpinestars Nucleon Flex Plus shoulder and elbow armor to keep riders protected internally and externally. An additional pocket for the Nucleon back protector (sold separately) provides the option for all around coverage. The SMX Air is also tech air ready for another layer of protection. Sizing: Customers find this jacket runs small and recommend sizing up one size from what size chart suggests Video model Gabrielle is 5'4, 120lbs with a 27 US jeans / vanity size, 28 natural waist at belly button, and 33.5 bust measurement Gabrielle is wearing a size SM jacket Features: A 2-3 season sport jacket with generous airflow and included windproof liner for cooler rides Updated graphic styling and race-look DFS hard shoulder sliders in a lightweight Class A rated street package Tech mesh chassis with mechanical stretch combined with 450D polyfabric perforated in key areas including the chest panel Strategic stretch inserts on side torso and upper back panel Ergonomic design for optimal sport movement and flexibility Fully CE-certified riding garment to CE Category II EN 17092-4:2020 standards A class CE Level 1 En1621-1:2012 Alpinestars Nucleon Flex Plus shoulder and elbow armor Tech-Air Ready Detachable windproof liner Waist adjusters Waterproof compartment DFS lite external shoulder protectors New inner construction for Nucleon protection insert (sold separately) upgrades and ready to accommodate a back protector insert Note: This jacket is NOT compatible with the Alpinestars Nucleon Plasma Full Back Protector.