Engineered for ROAD riders, the Nucleon Plasma Back Protector Insert is Alpinestars’ motorcycle back protector insert delivering lightweight, sustainable impact protection. CE and UKCA certified to EN 1621‑2:2014 Level 2, it features Nucleon Plasma Technology—an eco‑friendly bio‑based blend with high‑performance polyurethane—plus extensive perforations and ventilation channels. Ultra‑adaptive geometry compresses and extends to fit, improving coverage, airflow, and all‑day comfort inside compatible jackets and suits; offered in three waist‑to‑shoulder sizes.