A small adhesive bandage used to protect minor cuts, open sores, and other such injuries from getting infected. It should be noted that Band-Aid is a registered trademark owned by Kenvue, a consumer health company spun off from Johnson & Johnson in 2023. J&J had a history of adamantly protecting their trademark from being genericized.
The UK and Australian counterpart would be Germany company Beiersdorf AG's Elastoplast, itself used as a genericized trademark in those countries despite still being active registered trademarks like with Band-Aid.