Alpinestars GP Pro 2-Piece Suit 1.3mm full grain leather. PU external sliders on the shoulders, elbows and knees Aerodynamic, dual density back hump. Lateral accordion stretch panels across the back. Accordion stretch panels on the elbows and knees. Aramidic stretch panels in the sleeves and crotch. Alpinestars patented calf expansion pockets improve range of fit Removable mesh lining with stretch panel inserts work with outer stretch zones for a snug fit. Removable CE certified GP elbow/shoulders protectors. Removable CE certified GP-R knee/shin protectors. Chest pad compartments with PE protection padding (Alpinestars Bionic chest guards available as accessory upgrade). Bionic Back Race snap connection system. Replaceable Sport knee sliders. YKK auto locking zippers.