Anna Haupt and Terese Alstin two design students from Sweden have created useful and safety ‘Hövding the invisible bike helmet’.The collar contains an airbag that will inflate and protect the head in the event of an accident. Wearing a bike helmet is annoying. Bike helmets are a pain to carry around and get sweaty or ruin your hair. But they can also save your life. Industrial designers Anna Haupt and Terese Alstin decided to solve the problem when they began the design process for an invisible bike helmet in 2005. Spend 7 year and now, the helmet is here and it’s available for purchase in Europe and they’re not cheap. They cost 399 euros each. Is worth to buy if it saves your life.