Oxford PSI Alert Motorbike Valve Cap Correct pressures are critical to the performance of your tyres, which are in turn critical to the handling and safety of your motorcycle. The Oxford PSI Alert motorbike valve cap is the perfect way to stay on top of your tyre pressures with zero effort. Simply replace your existing valve cap with an Oxford PSI Alert pressure valve cap, selecting the lowest PSI limit nearest to the bike manufacturer’s recommended tyre pressure. The colour changing valve cap indicates tyre pressure loss: Green = Optimal pressure Yellow = Slight drop in pressure. Red = Significant drop in pressure - inflate tyre Motorcycle Valve Cap Features: Brass material. Metal pin cap. Alerts you of pressure loss. Sold individually. Available tyre pressure versions: 29-30, 31-34, 35-37.