These unstudded all-season tyres from Continental have a diameter of 17". The tyres play quite a significant part in the overall safety of your vehicle, so don't cheap out on those.
From Protyre
Continental TKC 70 Rocks 150/70R17 69S | Protyre - Car Tyres
Tirendo
Continental TKC 70 Rocks ( 150/70 R17 TL 69S Rear wheel, M+S marking, M/C )
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