Vintage Electro Products Co. “Electro Duo Exhaust Analyzer” designed for Butane/Propane exhaust analysis and air‑fuel ratio tuning. This mid‑century diagnostic tool was used in automotive and industrial combustion testing before modern electronic analyzers existed.
This unit includes:
Original metal case with worn red/black paint and strong patina
Large analog air‑fuel ratio gauge with dual scales
Butane/Propane mixture scale prominently featured
Factory instruction panel with SET / TEST procedures
Toggle switch (OFF / SET / TEST)
Two adjustment knobs
Internal storage compartment with coiled sample hoses
Made in U.S.A. – Electro Products Co., New York
Brand: Electro Products Co.
Model: Duo Exhaust Analyzer
Fuel Type: Butane / Propane (also Gasoline scale)
Country/Region of Manufacture: United States
Type: Vintage Exhaust Gas Analyzer
Condition: Used, untested, sold as‑is
Era: Mid‑20th Century