There was insufficient public education about items that are restricted on board a plane. i had a 3kg weight in my carry on baggage which was taken away in the premise that it has the potential to harm someone on board. I am disappointed that there were no clear information that states that ‘heavy' items are prohibited on board & i don't see how a weight has the ability to harm someone. This has caused great inconvenience for me & i am disappointed to be met with a less than patient service staff who showed annoyance because he couldn't understand English & is unable to converse in an international language fluent enough to make this whole process easier. I hope that Incheon airport can work on this to prevent similar disappointing events from happening & get back to me asap. sincerely, an angry passenger