You wouldn't think that .0625 of an inch would make a big difference, but when it's a change in the diameter of the ball on the end of the barbell through your tongue (1/4 inch to 3/16 inch), let me tell you, you can really feel it. I keep momentarily panicking, thinking the ball's come off or something, because it doesn't feel the same against my tongue and the roof of my mouth. New thing learned for the day (which actually could probably have been learned by more thorough reading of the website): Barbell ends from Leroi come packaged singly, not in pairs. Good thing I had ordered one blue and one purple. Now I have a multicolour tongue, just like I have a multicolour head.