When traveling internationally by air, there are certain items and substances that are generally prohibited or restricted to ensure safety and security. It’s essential to be aware of these restrictions to avoid any issues during your journey. Here’s a list of items you typically cannot carry during international flights:

1. Weapons: Firearms, explosives, and sharp objects such as knives, swords, and martial arts equipment are strictly prohibited in carry-on luggage. These items should be declared and packed in checked baggage if allowed by the airline and destination country.
2. Liquids and Gels: There are restrictions on carrying liquids, gels, and aerosols in your carry-on baggage. Containers must be 100 millilitres (3.4 ounces) or less, and they must be placed in a clear, resealable plastic bag. Exceptions include necessary medications and baby formula.
3. Hazardous Materials: Items such as flammable liquids, gases, toxic substances, and chemicals are typically not allowed on flights. This includes items like paint, bleach, and certain batteries.
4. Sharp Objects: Sharp items like scissors, razor blades, and tools are often restricted in carry-on luggage. It’s best to pack these in checked baggage or leave them at home.
5. Self-Defense Items: Items like pepper spray, stun guns, and similar self-defense tools are generally not permitted in carry-on luggage. Check with the airline and destination country for specific regulations.
6. Explosives and Incendiaries: Any form of explosive or incendiary devices, including fireworks and flares, is strictly prohibited on flights.
7. Sporting Equipment: Some sporting equipment like baseball bats, golf clubs, and hockey sticks may be allowed but should be packed in checked baggage. Check with the airline for their specific policies.
8. Large Liquids: Containers with liquids larger than 100 millilitres, including full-sized bottles of shampoo or lotion, should be placed in checked luggage.
9. Illegal Drugs and Substances: Possession of illegal drugs, recreational marijuana, or controlled substances not prescribed to you is illegal and strictly prohibited.
10. Items Restricted by Destination: Some countries have specific restrictions on items like certain foods, plants, or animal products. It’s essential to research and adhere to the regulations of your destination country to avoid issues at customs.
11. Electronic Devices: While most electronic devices like laptops and smartphones are allowed, some airlines may have specific rules about their use during the flight. Make sure to follow any instructions given by the airline crew.
12. Pets: If you’re traveling with pets, there are specific regulations and requirements for transporting them internationally. Check with the airline and the destination country for their pet travel policies.

Remember that airport security regulations can change, and the specific rules may vary depending on the airline and destination. Always check with the airline you’re flying with and review the guidelines provided by airport authorities to ensure a smooth and hassle-free international flight.