When you hand over a $100 bill at a store, it’s not uncommon to see a manager hold it up to the light to verify its legitimacy. But what are they looking for? There are a few subtle features on larger bills that are designed to protect against counterfeiting.

To find out how to make sure a bill isn't a fake, dive into this infographic from On Stride, a financial services company based in the UK. It covers the basic security features of both dollar and pound bills. Remember: Always look for the watermark.

Courtesy On Stride