The MX333 known for it’s incredible fit takes it to the next level with our all new sole and now featuring Carbitex arch suppor t panel for a more secure fit. Lighter weight and more durable the new MX333 is perfect for any type of racing. Upper: Light weight Clarino Microfiber or Extemely durable helcor leather upper with Carbitex Medial Support panel for a secure fit. Outlast temperature regulating heel & tongue liner. Internal Thermaform Carbon Fiber heel counter. The MX333 draws from the same Thermaform technology as found in the CX403. The Internal heel counter is heat moldable carbon that gives the option to better customize the heel hold. A secure heel hold will stabilize the foot and eliminate heel slip. Stable foot allows for more power transfer and less fatigue. Closure: BOA® Fit System featuring Dual-Dial Li2 with releasable lace guides. There is not one element that can take credit for shoe fit. The dual BOA® fit system is not unique to cycling but it is how we use this dial system in conjunction with out pattern work, our world class shoe Last and selection of superior upper materials that make this system work and why Lake shoes are known across the world fo r being the best fitting and most comfortable high performance cycling shoe.