Dang I forgot to measure. They fit perfectly inside both sets of my DB's. One set is the solid cast style like you can buy anywhere and the other is a gym style set with metal handle and rubber covered weights made by Troy I think. I am nursing a pulled rhomboid so I didn't do anything crazy with them this morning. I cranked out 4 sets of 12 Zottman Curlz with the ole Fat Gripz and you no what it was tough. My forearms were on fire when I was done. So first run through they felt great in my hand and they worked for something simple, I am looking forward to good things with them.
My buddy had a hard time pulling them off the DB's when we were done so the fit is tight and secure.
What we think, or what we know, or what we believe, is in the end, of little consequence. The only thing of consequence is what we do. -John Ruskin