Seth Lee Jones - Hipshot Slider.
If by any chance you haven't listened to Seth Lee Jones play guitar yet, be sure to check out his page along with this nice article spotlighting his unique playing and slj guitar.
I can't hide that I'm a big fan, and it's always great for me to see Seth using the Diamond Bottlenecks 'Ultimate' slide that we sent over to Tulsa for him. Once of the finest slide players around, and incredible all round player to give credit where it's due. He's also a great luthier, so check out his work and have a look at this article.
The slide Seth is using is a Blue w/Yellow Swirl Lead Crystal 'Diamond Bottlenecks Ultimate', we spent a while making sure the dimensions of the slide were suitable to him. But once I had one that matched his requirements to the mm, I sent it over and he's always posting up videos and photos of his using it, which is a great feeling for me as a fan.