The reason for this is to ensure a proper break-in, coating the bowl with a carbon lining from the bottom up
Bugs Eye View (Mississippi State University) 1 2 3 "A laboratory study of Stegobium paniceum (L.) (Coleoptera : Anobiidae)"
Though these are allowed in checked baggage by IATA but specifically when you are traveling to the US, this kind of stuff is totally banned in case the cylinder is not empty
Cigars: Like cigarettes, cigars also contain nicotine, although in varying amounts depending on their size and type
6.2 Artificial intelligence-based intelligent regulation With the rapid development of artificial intelligence technologies, such as artificial sensors, spectroscopy, computer vision, digital image processing, machine learning and big data analysis, it has become feasible to quantify temperature and humidity changes, as well as succession patterns of microbial communities during the fermentation of cigar tobacco leaves (Yang et al., 2023)