The existing Huber records are handwritten documents in two separate books, a sales register & a build records book. Neither book is complete. Between both books we can often provide information on many existing Huber tractors. When Huber completed a tractor it got the next sequential serial number. If they were only building one model at a given time the number for that specific model ran sequentially. When the company was building multiple models of tractors at the same time the next completed tractor got the next number. Now when we research an individual tractor model it can be a tedious task to determine how many total examples of a model were built as the task will likely mean scanning several years’ worth of total tractor production records. If I ever miscounted when doing my research let me apologize in advance now. Happy Hubering. MSS