The TSG Evolution Skate/BMX Helmet has the following features: This TSG helmet for adults is no excessive luxury. A skate helm serves as protection for your head when you might crash or fall. The helmet has an adjustable chin strap with snap closure and multiple openings for ventilation. The lining stays in place with velcro and comes in two different thicknesses. Specifications: TSG skate and BMX helmet for adults Removable lining Openings for ventilation ant the top, front and back Adjustable chin strap with snap closure Which size do I need? Size S/M: 54-56cm Size L/XL: 57-59cm Size XXL: 59-60,5cm Tags: helmets, protection, skate helmets, BMX helmets.