Unfortunately our pen-grip mice only have right-handed models at the moment.
Since the shape is optimized and tuned for the right hand, we don't recommend using them in the left. But we do have a number of users that are left-handed and nevertheless use our mice in their right hand and have commented on how comfortable and natural it is.
If there is enough interest in left handed models we may produce them in the future. But this is not something we are working on at this stage