I found an old walk behind aerator for sale. I have never seen one quite like it. It has a 3.5 Briggs, 3 or 4 large drum like wheels with tines, they must be 2 feet high at least. The drums like wheel things drive the unit. In front of the drums is one single castering wheel. Behind the drums are two transport wheels. The unit is very tall and heavy. Probably about three and a half to four feet tall. It appears to have been red at one time, but now is painted green. Coring width appeared to be around 19 inches(no tape with me that day). Anybody have any idea who built this thing? If so, how well do they work? The unit in question is being sold on commission. The guy said the owner wanted $400 for the aerator and a powerrake, but was probably negotiable. I offered $100 for the aerator. The guy was going to check back with the owner.