TRR-S Convert Red TRR-S is the HPC helmet available in two different shell sizes and is designed to provide maximum comfort to the trialist, for those who prefer the road. Its advantages are that it is lightweight and has optimal ventilation. Included in the package you will also find the convenient removable covers of the top air vents that provide maximum protection even during the most humid days. The inner lining are made with utmost care and provide unsurpassed comfort. The modern design and its bold graphics give this helmet a unique style and personality.