Alfa Romeo 4C Owner's Handbook Manual page 177

RIMS AND TYRES PROVIDED
141)
Front tyres
Rear tyres
Reduced size snow chains with a maximum projection of 7 mm beyond the tyre profile can be fitted only on 235/40 R18 rear
tyres.
235/35 R19 rear tyres cannot be fitted with chains.
141) If winter tyres with a lower speed rating than that indicated in the Registration Document are used, do not exceed
the maximum speed corresponding to the speed rating of the tyres used.
Rims
7JX17 H2 ET 33
7JX18 H2 ET 33
8JX18 H2 ET 44
8.5JX19 H2 ET 49
WARNING
Tyres provided
205/45 R17 88Y XL
205/40 R18 86Y XL
235/40 R18 95Y XL
235/35 R19 91Y XL
Snow tyres
205/45 R17 88Y XL M+S
205/40 R18 86Y XL M+S
235/40 R18 95Y XL M+S
235/35 R19 91Y XL M+S
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