The Acavallo Arena Alupro stirrups are characterized by the new, patented, laterally opening stirrups based on several years of extensive research and development. High-tech combination of metal and polymer materials, produced by means of an innovative, patented injection moulding technique. Due to its design and construction which is based on flexible polymers, the stirrup conveys a less rigid and much more comfortable feeling to the rider than with conventional products.The upper part of the footboard is in stainless steel and is characterized by long horizontal holes that prevent the accumulation of sand and dirt, so as to guarantee an optimal grip in all conditions; stainless steel also protects it from corrosion and therefore guarantees a long product life. The opening of the stress-actuated locking and release mechanism is located a centimeter higher from the tread to ensure that the foot cannot slip out laterally by mistake and to prevent sand and dirt from delaying the opening action of the arm in case of an emergency.