The tardiz helmet is designed for triathlon and like the dr39s phone box will help you move through space and time features a magic buckle closure which will be quick in transition and simple to use sunglass friendly ear pads flex for quick entry and exit rollsys retention system for the prefect fit and easy adjustment in mould 2 layer construction 6 cooling vents for cooling plus the aquavent which can be used to dump water through the top of the helmet for cooling this passes