yes, it increases the girth and the length. I had a different one but this one was enough sensation I couldn't hold back and came in it. Not to mention that less stimulation means I can last a bit longer. It isn't like I am cumming in 3 seconds but if I start really going hard and deep it won't last as long and sometimes I'm sure my wife just "wants fucked" and a big cock and some added stimulation helps that. I'm not a drinker so I can't get a buzz and go at it for 50 minutes straight anymore.
Err - Cock ring? Viagra?
Just bang 1/2 a viagra, get her to give you some you time first with a blowy, return the favour to her, & you'll soon find you can go again, with or without an extension.
4 inches does seem like a lot! If she likes the extension, she'll repay the compliment with some good oral. If not, don't do it.
I always think a lot of guys are trying to please on here without getting anything back. It's a 2 way street, & whilst you may think you're getting off on it too, it becomes old hat very bloody quickly.
Make sure that she's an active particpant, not just a recipient. The best women are those that try & give you the best experience too.