SP-X BOA Boots - Black/Silver - EU 45 - SP-X boots are a sleek sport boot designed to fit under tech riding pants and provide superior walking capability - Optimized for the sport and sport touring rider, the SP-X are compact, mid-height boots with premium levels of protection and comfort on and off the bike - The upper is constructed from a combination of Rideknit® material and knitted mesh, plus seamless thermo-welded parts - The lower features a TPU heel counter, toe slider, and the Alpinestars Transversal Protection Frame (TPF) on the sole, allowing for high levels of protection against impacts and any bending or twisting - Additionally, the sole also features an all-new design with an asymmetric back heel to facilitate the rider's natural stride and promote off-bike stability - For protection, the SP-X has an integrated shin impact protector, dual-density ankle discs, plus TPU shift pad and toe slider reinforcement - For comfort, the knitted areas on the front and back flex points offer great freedom of movement, while the PU midsole with integrated double cushioned heel compound and removable OrthoLite® insock, provide great walking comfort - In and out is facilitated by a medial zip combined with the BOA speed lace system for compact and precise closure - SP-X boots are perfect for those sport riders looking for coverage and protection but without the full race boot, over the pant look