Up for sale is a Vintage Sears External Tank-Type Engine Pre-Heater with Thermostat (120 Volts) and a Vintage Sears Anti-Freeze Tester with Glass Barrel.

Neither appear to have been used, and appear to be complete.  Each comes with instructions. and original packaging. Neat items for a man cave or anyone putting together a vintage garage. I would guess that these are probably 25-30 years old.