Tyres and wheels
https://vehicleinspection.nzta.govt.nz/virms/in-service-wof-and-cof/general-trailers/tyres-wheels-and-hubs/tyres-and-wheels
designed to give a visual indication of the degree of wear of the tread. To help locate these on a tyre, inspectors should look for a ‘ ’ or ‘TWI’ mark on the outer edge of the tyre side wall (most tyres have these marks). Tube means an inflatable elastic liner, in the form of a hollow ring fitted with an inflation valve assembly, designed for insertion into certain tyre assemblies to provide a cushion of air or gas that, when inflated, supports the wheel (also known as an ‘inner tube’). Tyre