Good Lord !!!
That is a 16X16 Roll Top Machine. These were very popular in Churchs, Club House, Luncheonetts, and Snack Bar Kitchens. Vulcan bought out the Colt Autosan Company around 1964 ? (stevet) and were Vulcan Autosan,I'll say until around 1973-4 ? (stevet). These machines were Mediocre at best cleaners except for the Hobart SM series. (Hobart had the SM which is like the one in the pic(16X16 Rack) and they also had the LM which was a (19 3/4 X 19 3/4 rack). The reason why Hobart was better in this series was they had a Revolving Spray Arm on the Bottom of the machine where the Insinger, Colt AutoSan, Toastmaster, and Champion had a Staionary Spray Arm. The theory in Commercial Dish Machines is "The Water has to Move, Or the Dishes Have to Move". Meaning, a Door type machine where the rack sits stationary must utilize moving water for Excellent Cleaning results. The Stationary Spray arms are applicable for a Rack Conveying Machine. (The Spray Compartments are Stationary but the racks are moved by a Conveyor System through the Different Wash and Rinse Chambers.
This Machine is I'll say from the Mid to Late Sixties. Good Little Sanitizers providing they had a 180F Booster heater for the Final Rinse. I believe they had like a 80-90 second wash, 5 second dwell, and 12 second Final Rinse.
They are Cute Little Buggers aren't they ? Sort of looks like a Lunch Box !