Nothing written on the Switch other than AIR on the Switch lever itself. Here are a few more pics. of the Switch.
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thumbnail (74).jpeg (51.98 KB, 191 downloads)
Heater Switch in 53 Chevy Panel Truck
thumbnail (75).jpeg (47.86 KB, 190 downloads)
Heater Switch in 53 Chevy Panel Truck
thumbnail (75).jpeg (47.86 KB, 190 downloads)
Heater Switch in 53 Chevy Panel Truck
thumbnail (76).jpeg (51.32 KB, 190 downloads)
Heater Switch in 53 Chevy Panel truck


1953 Chevrolet 1/2 ton Panel Truck 3100
4800 LB. maximum rating, 85hp at 3300 RPM