They seem like different colours but could be based on the way the nap in the carpet is going.  I am unsure of how to secure them to the steps   Double sided sticky tape Nail them  No instructions.  Overall satisfied with product but that’s based on not having tried them out and knowing I will have to use my own ingenuity, just for the price I expected at least some direction.  These are for our painted stairs into the basement, attempting to make it less like a dungeon, so this will do the trick, for anywhere nicer they’d be being sent back.