I bought this for my 26" MTB. Turns out that the description is incorrect and the one advertised is for a 29". I ended up giving it to a fellow rider and bought the M1 (elsewhere) for the 26" MTB.
The fender looks great on my bike after a couple of minor adjustments to the mounting hardware to get it even with the tire. It has a lot of coverage for a 2.5" tire and keeps the spray down pretty well. I also have the M2 for the back, great fender.
The mounting bracket and hardware is OK but not optimal. A couple of size options for the frame tube would be nice as I had to trim down the tube insert to get it to fit my bike. The bracket and fender attachment points are a bit wobbly (fixed with gaffer's tape). Also, The plastic bracket where the fender attaches WILL snap off if it is tweaked against a tree just right (also fixed with gaffer's tape).