Whatever the journey, Aertis is there to make it easier and better. The comfort of a premium suede construction meets the Firmor Closure technology to offer great lateral support. The nylon sole with replaceable rubber insert allows for maximum grip in any situation and increased walking comfort. -Designed for maximum lateral support the Firmor Closure contours the foot with a solid hold, and allows infinite size adjustment for the ideal individual fit -The Sidi Mega Last provides Sidi fit and performance to riders who have slightly wider feet -The Sidi Mega Last is 4mm wider across the ball of the foot, has more volume, a higher instep and a wider heel cup -Mega lasts are sized EE to EEE -Sidi's Tecno-3 System dials in fit along the entire length of the shoe, adapting the upper to the shape of the foot for a customized fit -The closure uses a new proprietary SIDI Wire monofilament that is completely non-binding for intuitive and effortless on-the-fly adjustments -Like most Sidi small parts, the Tecno-3 System is serviceable and replaceable -The Sidi MTB SR17 sole represents the ultimate result in terms of stiffness for pedaling and flexibility for walking -The toe inserts are easily replaceable and offer the possibility to mount spikes for particularly muddy rides