I like using their pin because it tightens down the rack to the hitch and reduces any shaking. The cool feature I found after I received the product is the watch charger can taken off. I have had these slippers for about a year now and recently bought another pair of the same fox ones as a gift. I think the correct size order should be: "Little Kid 6, 10, 11, 12, 1, 2, 3, Big Kid 4, 5, 6". We only have a few wears left in the shoes before it will be off completely and they will no longer be functional. La carica dura abbastanza, dipende sempre dalluso del volume ma per me che li uso più che altro in auto o quando sono a casa vanno più che bene, anche perché la carica è abbastanza veloce. the parts are the same that come with the Hellcat figure. Was very happy when they arrived pugged them into my computer and got them all charged up. UPDATE: major design flaw. a smartphone which allows you to control the the pairing process in a more user friendly way.