Read Trevor's review and believe him. I didnt and purchased. Its impossibly tight and a waste of money.
Theres no way to fit into it without a lot of pinching. The internal diameter is just far too tight. 45mm or above.
Save your money and buy something else
Excellent looking weighted ball stretcher..
This product looks great & the weight is fantastic pulling down on your balls. That's as good as it gets! The inner diameter of just 35mm is so tight I struggled to get my nut sack in without terrible pinching when tightening the bolts. It should be a minimum of 45mm inner diameter. Also the inner edges are too hard angled and need to be more softly curved as they really painfully dig in to your balls. I can't wear this device for more than 30 minutes, the pain is so bad. I do not recommend anyone buying this product.