[John_K_348]

Are they Hex head and what mm?

 

[lockem]

Are they Hex head and what mm?

Eurocompulsion says that they are 14x1.5 threads and that "standard" nuts work with their stud kit:
https://shopeurocompulsion.net/coll...otis-la-black-zinc-stud-kit-alfa-romeo-giulia

Ebay dude's replacement lugs are hex head and take a 17mm wrench:
http://www.ebay.com/itm/20-black-Ex...MW-/272421406464?_trksid=p2141725.m3641.l6368

Centerline includes a wrench with their deluxe stud set:
https://www.centerlinealfa.com/catalog/titanium-stud-conversion-giulia

None of which exactly answers your question, but I suspect that 17mm hex is a very good bet if you are looking for the correct lug wrench for the stock bolts.

 

[John_K_348]

OK great, so the outer tool geometry is still standard socket type. I could have sworn they were spline or hex head (Allen) or some other newness beyond the Italian bolt style like Ferraris. After closer inspection online I see that the heads are just bored out to save weight. My lug bolts form the 348 and 360 were solid, rounded and chromed.