Say you go to the refrigerator store and they are selling fridges for $100 each, limit 10, or as stated in this store, limit $1000 in fridges. You give them $1100 to buy 11 fridges. They refund the excess purchase, which would be $100 or one fridge. At least that's my logic here. I feel like the excess purchase is that extra $25 plus the third transaction. But who knows, honestly? It's probably tied up in some barely-known financial law and can only be purchased with exact figures.