RNF means that a tyre is reinforced. These tyres have historically been reserved for fitting on to small vans, people carriers and 4x4 vehicles with the odd estate car having them also. However there has recently been a rise in manufacturers such as Renault and Audi using a new style of reinenforced tyre. On high-end models they come as original equipment, and have a lower profile and offer higher performance. Due to their extra load carrying capability and rigidity these tyres have enhanced road handling.