I ordered this thin one for Jazz, 3/8" here:http://www.allk-9.com/super-soft-premium-leather-dog-leash-with-braided-ends-p-829.html
Unfortunately, while it was 3/8", it was double layered, which you can kinda see in the pic now if you look, o too heavy for a small dog. It is soooo soft though. I would have had no heitation using this leash for Max, it's a nice leash, particularly for the price! It does have a slightly longer hand loop than most, and it's not riveted, which one review says it is. If it weren't for the thickness, it would have been be the perfect leash.
I was able to get a new thin leather leash through the women that makes them for my trainer, but she is going out of business, so I stocked up on a few extra.