The screw holes did not line up properly on a few of the pieces. Would have been okay if I just got the grease. The product does exactly as advertised and is made with high quality enough materials that it hasnt shown any signs of wear with regular use for several weeks. lol . Charges fast though. Granted the Anker is a variable, but Im not buyin it. Very useful for me b/c the ancient elliptical trainer squeaks so much. Im still wearing them after 2 1/2 hours and my feet dont hurt, normally that short period of time has me in pain. 5, and they fit great! Size 39 fit perfectly.