FEIFAN 31.8mm Mountain bike MTB half carbon stem Aluminum Carbon Fiber Bicycle Stem 90mm 100mm 110mm

The product works like it should, however when it arrived two of the four bolts were way too tight. I got one of the first 2 came off without a problem, the 3rd one I got off with an Allen wrench, the 4th started to strip and I had to use an impact wrench to get it started, and yes I was using the correct size Allen wrench.