I also have them. I think 3 checks of USD 20 each. (Mine are American Express, though) 20-30 years ago this was the only way to travel intercontinenal. After the trip you did not exchange them back (in Europe) because both buying new ones and cashing old ones involved fees. The last 10-15 years cards have become mostly universal, so it gets less easy to spend them. It thought using them on my last trip to Australia 3 years ago, but I didn't happen to hit a suitable place accepting them, so I brought them back again...
