These are very cute and work great for giving more grip for a new crawler.  The difficult part is putting them on and taking them off.  My wife modified ours by slicing them up the back then sewing new seams with velcro strips.  Now we put them on easily compare to our daughter thinking we are putting more clothes on her, which she kinda dislikes doing.  We could definitely see how much better our daughter was able to crawl across tile and hardwood floors compared to just doing in place exercises.