If you're going to list an ad for a steering wheel, at least post the size. Even better yet, post a picture with a tape measure held up to the outside diameter. The first question asked in almost every ad for a steering wheel is about the diameter. I understand that not everyone has a metric tape measure, but at least use an imperial one and convert it. Here's a picture and estimated chart for quick reference.
320mm ≈ 12.60"
325mm ≈ 12.80"
330mm ≈ 12.99"
335mm ≈ 13.19"
340mm ≈ 13.39"
345mm ≈ 13.58"
350mm ≈ 13.78"
355mm ≈ 13.98"
360mm ≈ 14.17"
365mm ≈ 14.37"
370mm ≈ 14.57"
375mm ≈ 14.76"
380mm ≈ 14.96"
385mm ≈ 15.16"
390mm ≈ 15.35"
395mm ≈ 15.55"
400mm ≈ 15.75"
Both Starrett and Mitutoyo (pictured) make excellent metric tape measures and you can pick one up at a local industrial supply store or a good hardware store.
320mm ≈ 12.60"
325mm ≈ 12.80"
330mm ≈ 12.99"
335mm ≈ 13.19"
340mm ≈ 13.39"
345mm ≈ 13.58"
350mm ≈ 13.78"
355mm ≈ 13.98"
360mm ≈ 14.17"
365mm ≈ 14.37"
370mm ≈ 14.57"
375mm ≈ 14.76"
380mm ≈ 14.96"
385mm ≈ 15.16"
390mm ≈ 15.35"
395mm ≈ 15.55"
400mm ≈ 15.75"
Both Starrett and Mitutoyo (pictured) make excellent metric tape measures and you can pick one up at a local industrial supply store or a good hardware store.