It is a 'standard' 10K pot (i.e. with 300 degrees of mechanical travel) but with the active part of the track (i.e. the pactiula resistive track) occupying only the center 50 degrees of the mechanical travel.
It has a 6mm diameter shaft and is normally used in our Fingertip throttle mechanism.
It is not recommended for operation from radio control servos which require a track of more than 90 degrees!
$7.00 
Fingertip Throttle Mechanism