Alpinestars A-1 PRO Chest Protector The A-1 Pro Chest Protector features a Level 1 CE and UKCA Certified Polyhedron Hybrid Technology chest and Polyhedron Technology back protector that offers unsurpassed Levels of ventilation, is super-lightweight and delivers excellent upper body protection against impacts. Lightest CE Level 1 Chest Protector weighs only 664 grams in size M/L. 18% of the chest protector’s structure consists of ventilation apertures and these are aligned through both layers of the hybrid structure to ensure maximum ventilation and airflow. Ultra-ventilated with ram air plenum directing heat build-up away from the chest. Flexible chest protector molds to the chest shape for an adaptive fit. Anatomically profiled back protector is contoured to follow the natural curves of the spine for superior comport. Adjustable and removable shoulder padding for a customized fit. BNS compatible via elasticated BNS pull tabs.