Tether upgrade kit to convert your HANS device to sliding tethers that offers improved freedom of movement without compromising protection. Hans Device Sliding Tether kit comes with all parts to convert one helmet and one HANS device. HANS recommends that tethers be replaced every 5 years or after a major impact. Post anchor tether. 18"/450mm tether length comes standard with all Hans devices and works in most applications. This kit is for the HANS Sport III models only.