Annex II of Regulation (EU) 2020/740 mandates a minimal label size of 75x100mm.
Any technical promotional material shall display the tyre labels. No requirement on the size for the labels displayed electronically is specified. In particular, Article 4.2 and 6.7 read for tyres sold or offered for sale by distance selling 'The size of the tyre label shall be such that it is clearly visible and legible and shall be proportionate to the size specified in point 2.1 of Annex II.'
Moreover, it is technically impossible to respect a size in millimetres or centimetres on an electronic screen because the size varies depending on the 'resolution' of the screen.
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