I purchased these aero bars to add onto the existing bull-bars on my Specialized Langster single-speed. A bit odd, I know, but with the initial coronavirus lockdown instruction of only exercising locally, rather then beast my "bike for best" the single-speed provided great training on a local 35km road lap. The bars are very well made, allowing three width settings for the rest pads plus the ability to rotate the pads to your own specifications. Bear in mind that bars are a tight fit onto the noted handle bar dimensions. As I did not have any bar tape to fiddle with, the attachment was straightforward, but the tolerance is tight. However, I was able to place a strip of old inner tube between the existing bars and the aero bars to prevent scratching and to add a little extra purchase. Be careful when you tighten the 4 x locking nuts (2 per bar) as I was almost tempted to over tighten the bolts which would have possibly stripped the thread. It takes a bit of fettling to get the width of the aero bars and the placement of the rest pads just so, but it's worth the work. After my first couple of rides, I always checked the rigidity of the bars and tightened when necessary. Note that you cannot extend the reach of these bars as you can with other models, but this hasn't been a problem. I especially like that my wrists are bent, as if gripping normal drop bars in a "race position" when in the aero position as opposed to being in line with your arm. This seemingly gave me more steering control and greater comfort over a ride. There are cheaper models out there, but the high level of engineering, straight forward instalment and the difference these aero bars have made in terms of speed and riding position comfort certainly justifies the price.