I use a universal vista for 1" bars. It took just a little modification but works as intended. I installed the thumb lock upside down. If you install it as directed, the thumb lock will be 'up' while unlocked. I figured since it will be unlocked most of the time, I'd rather it was down. So to lock the throttle, I flip the lever up. To take it off, I flip it back with my index finger, like pulling a trigger. It's almost a natural movement coming off the throttle.

Vista unlocked



Vista locked



Made a reaction arm from scrap aluminum as the supplied was too long. Attached it to the throttle cable retaining screw. Bad photo too close up.