If "21681" alone yields too many results, search for the specific agency (e.g., "FAA 21681 PDF"). Battery guidance document - IATA
The official guide is available at IATA.org . Option 3: Other Technical Standards If neither of the above fits, "21681" might refer to: Download 21681 pdf
Detailed requirements for shipping Lithium Ion, Lithium Metal, and Sodium Ion batteries by air. If "21681" alone yields too many results, search