We had a generic, 2" extender that was 1.75" thick near the base. It was made of silicone and made my length 8 1/2". It was very comfortable to wear when lube was applied. My wife loved the full feeling, but it developed a split after a year of use. I'm ordering a new one from BlissfulCreations on Etsy. They have great ratings, decent prices and look to be well made.