Troller Autopulse Transamp 20 HO N Z Scale Model Railroad Train Transformer

Up for sale, a Troller Autopulse Transamp 20 HO N Z Scale Model Railroad Train Transformer. This transformer has been tested using a volt meter and appears to be working. It pulsates, as i assume it should? Never seen one before. Cosmetically in good shape as well. Box has heavy wear and age (See Pictures). Please Note: This transformer is being sold As Is. But, I would be more than happy to answer any questions or concerns you may have.