The $1 bill to keep an eye out for has an extremely rare (and valuable) serial number. This one-dollar bill might be worth thousands.

Another exciting find is double quads, where two sets of four identical digits appear, such as 11110000 or 88880000. These are in high demand among collectors.

Want to know more? Check out the Want List at CoolSerialNumbers.com to see if you have a bill they’re looking for. So, take a moment—check your wallet. You could be holding a bill worth far more than a dollar!