Product Placement Blog ➞ 3M3M Littmann Stethoscope in Chicago Fire S10E01 “Mayday” (2021)September 23, 2021 Sergey TV Show Hi! On Thursday, September 23, I watched a TV Show and product placement was spotted: 3M Littmann Stethoscope in Chicago Fire S10E01 “Mayday” (2021).