Single Tether Simple action Wichard Hooks A tether is the indispensable complement to an inflatable lifejacket, provided you have initially selected a jacket model "with harness", i.e. with stainless steel buckles and meeting the resistance requirements of ENISO 12401 standard. All Plastimo harnesses come with or without a tether, to allow all combinations. Elasticity : this model stretches out when needed and contracts when not under tension, which contributes to a greater freedom of movement and improved safety, as it is kept short and tidy to prevent accidental snagging. Strain indicator complies with ISAF specifications : When the tether is submitted to a heavy load (ex. man over board), the strain indicator exposes a label showing that tether should be replaced.