This is a big plug, but not too big to be of good use. The widest part is 2 5/8 inches in diameter, which is bigger than I normally put in.(2 1/4 goes easily in me).So I had to sit down on it a number of times and use some anal-ez to get it all the way in. But it was worth the effort and the initial discomfort to feel my ass close down around that neck. What a great feeling! I'm going to keep using this one as my trainer, so that my capacity doesn't diminish. No doubt I recommend this to anyone who likes "size". Well worth the price!