American Optical 1791 Duo-Check Coolant and Battery Tester Box Instructions

American Optical 1791 Duo-Check Coolant and Battery Tester with Box and Instructions WHAT IS IT? American Optical Duo-Check Model 1791 handheld automotive coolant and battery tester, red plastic, with original box and instruction sheets shown. WHO IS IT FOR? Vintage automotive tool collectors, garage display buyers, and specialist testers/diagnostic tool collectors. DETAILS: American Optical branding and Model 1791 are visible on the tester and paperwork. Red plastic body with black end cap and clear clip assembly. Box and instructions are included as shown. Made in USA is printed on the paperwork. CONDITION: Good preowned condition with visible age wear, scuffs, toning, creases, and paper stains on the instructions. SEARCH TERMS American Optical, Duo-Check, Model 1791, coolant tester, battery tester, vintage automotive tool, garage collectible, USA made, red plastic, instruction sheet, original box, diagnostic tool, auto tester INV / BX INV: 337 | BX: B-J29 Colorado Sales Tax Notice: All sales within the State of Colorado are subject to applicable sales tax. The listed price does not include tax, which will be calculated and collected at checkout or at the POS register.