I bought 2 sets of day wear glasses from Specsavers and a pair of sunglasses all of which were Timberland frames. I’ve got to say that I am disappointed. On one of the pairs of day wear frames the arm broke about half way along. Over time, any flexibility in the arms diminished to the point that they broke if I attempted to manipulate the arm in the slightest way. Hopeless. They are either not UV stable or are sensitive to heat simply be being worn.
The sunglasses suffered a similar fate. The left had arm broke at the point where the metal section of the arm stops and becomes purely plastic. At the time I was riding my motorcycle and fortunately I had some race tape on hand and was able to splint the arm with a small stick so that it was usable.
If your intention is to use these specs while wearing a motorcycle helmet then avoid this brand. Find a different brand with more flexible arms(titanium preferably) otherwise there is a good chance you will have a breakage.