2011 Alpinestars SMX Plus Boots For superior safety and freedom of movement, the 2011 Alpinestars SMX Plus Boots feature an innovative Multi Link Control system and high modulus TPU protection integrated into the sleek profile of the boot. The inner Kevlar speed lacing closure and micro-adjustable ratchet fastener combine to ensure a comfortable, conforming fit on both the road and track. Forefoot laminated with shock absorbing open cell foam while the ankle area has a highly breathable lining for improved comfort. Alpinestars unique Multi Link Control System provides advanced support for the ankle, limiting hypertorsion, hyper-extension and hyper- flexion as well as providing additional impact protection to the ankle and Achilles. Wide, ventilated, heel counter extends to the ankle and is combined with a shock absorbing padded insert and self-molding foam ankle protectors. Replaceable heel slider and external side heel slider are positioned to dissipate shock and promote sliding during an accident. Newly designed, replaceable TPU toe slider with snap-in assembly provides more coverage around the toe area