Acavallo Arena AluPro Safety Stirrup Titanium ONEUnique, stress actuated locking and release mechanism located between the lower end of the outer, pivoting stirrup arm and the foot support plate tread Easy and reliable one click re engagement of the stirrup locking and release mechanism once triggered. 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 Considerable