Paul's Road Thumbies are shifter mounts that let you bring your shifters up from the down tube or your bar ends to the center flats of your handlebar, effectively turning them into thumb shifters. And, like all Paul components, they're made of 100% CNC-machined aluminum in his California workshop.
The Thumbies are only compatible with Shimano bar end shifters.
Also available in Silver (image unavailable from manufacturer).
Road Thumbies fit standard 26.0mm road bike handlebars.