Sidi T-5 Air Tri Shoes - Mens Black/Black 40.5Sidi T 5 Air Tri Shoes Mens Black Black 40. 5. The Sidi T 5 is designed specifically for triathlon. The upper weathers rain and water without losing stiffness and the closure system is easy to adjust and reliable the T 5 is particularly suitable for giving your best during triathlon competitions. The High Security Velcro closure is simple but reliable easy to adjust and fine tune especially on the bike The newly designed integrated heel cup is light