Glad it was a 2 pack or I would of went back and ordered another one. I wear them to school. I can do 14,000 steps a day while hauling weight going up over 100 flights of stairs 5 days a week and they will last for 6 months or more. Part A in the instructions is actually Part B. Time will tell how long they last, but these are very well made; the interior sole (which meets the foot) is firmly constructed and one solid piece. My dock doesn?t have cleats we have eye hooks. The straps are too short I think. These seems like a good slipper, they are for my 2. Only complaint is not loud enough! I have no trouble wearing them for a run or workout and not worrying about them falling out.