GY3. That is exactly the designation on my QTP's, but with none of the "Not for Highway use" signage like yours have.
Just as a friendly reminder to everyone, if ever an accident were to happen on a public road and your supposed DOT tires are not really DOT. It can create a mess. Drive carefully and try and keep clear of wet conditions. If it rains, pull off the road and wait it out.

A friend of mine for not listening to me crashed his car on the highway while wearing a pair of M/T Drag radials coming from a day at the track. The tires had plenty of tread on them but to no avail on a slight uphill 40 % turn. The road was slightly wet and he swung, hit the wall with the front drivers fender, swung again and landed on his passenger quarter, almost destroying a beautiful and fast car. Thank the heavens that he did not hurt anyone else. I had to block two lanes with my Diplomat police package while flashing the lights just so that he could clear himself of further danger on that blind curve.