Yes, you do need to drill 4 holes but it’s not too bad and pretty easy to do. They fit great comfy to walk in & heels usually are a little much for me. Auf meinem Mtb jedoch vollkommen unbrauchbar. I love my comfy crocs and was saddened when I broke mine. Por alguna razón, resaltaban las opiniones donde el producto es mediocre. The overall construction of these is quite good. The zipper, however, appears to be flimsy. Cons:Just a slight nitpick. I did not like the padding. A little annoying and would prefer this not happen, I dont like throwing my mouse onto my keyboard.