I ordered it straight from Jtek. Jtek seems like a one-man operation in the USA, and I feel like ordering direct probably puts more money into his pocket.

comes with a shim for 22.2 bars, a shifter cable, and the little piece that bolts on for internal hub shifting. The shifter bolts around the bar end, with a small bolt, that the instructions tell you not to overtighten coz stripping. Makes sense. The whole assembly doesn't look rebuildable, i.e. the shifter doesn't bolt onto the shifter pod. I'm not sure how it's attached.

As for function:
The biggest thing is: they shift to a higher gear when you pull up. So if you're used to normal bar-end shifters, it's opposite. Which is a little annoying if you switch between a bike with this and a bike with Shimano bar end shifters. I think if I did that on the regular, I'd have to switch to a Rapid Rise rear derailleur, to keep from going crazy.

I prefer the Shimano 'bent' lever shape to the straight shape on these. Feels better in your hand, man.

Also there's no barrel adjuster, which makes dialing in the shifting a little impossible. I had to install one of those in-line barrel adjusters that goes in a spot on your housing.
(visible in front of the headtube:)

Similar products used:
Shimano 7 speed Nexus trigger shifter- I had it mounted on drop bars up by the stem. I liked it a lot, maybe better overall than this. Not sure if the clamp design is still the same, to bend it onto drop bars.

It would be nice if there was a way to convert these to a thumb shifter too.