Here is a thread with information including CB & Honda shield thickness measurements, pictures of the shouldered mounting screw, etc....
2 years later CB is still making shields of incorrect thicknesses, sometimes thinner than original, sometimes thicker than original. If the thickness is not the same as the original
at the mounting holes, I would not accept it. The shouldered mounting screw is designed for a specified thickness of shield, anything thicker or thinner and the shield will not mount correctly with the original shouldered mounting screw. Measure it when you get one. Send it back if it is not the correct thickness.
I still have my unused thin CB windshield. CB sent me at no cost a correct thickness shield 2 years ago and it is still mounted on the NT. It now has a 1" crack at one mounting hole that was caused by me flying through it after being hit by a deer. I tried repairing the crack with an acrylic solvent but the crack is so tight little solvent was able to penetrate the crack. 1000 miles later and the crack hasn't grown. The crack in my correct thickness CB is clearly not a CB manufacturing issue....any shield could fail during an accident. Too thin or too thick of a shield is a CB manufacturing issue. Measure it when you get one. Send it back if it is not the correct thickness.
It's upsetting that CB can't seem to consistently make the proper thickness shield. But, knowing that, (and this is telling part of the story)
I would buy another one today if mines fails. And when it arrived, I would measure it, and send it back if it was not the correct thickness.