Advertising Backpack Sourcing Expert Needed

I'm in search of an advertising backpack that suits product promotion. The ideal backpack could either have a built-in LCD screen or flags, or be designed for outdoor walking display.

Key Requirements:
- It must be suitable for product advertising
- It should be lightweight and comfortable
- High visibility is a must
- Weather-resistant feature is essential

Please provide a bid if you have experience in sourcing such unique advertising tools.