I just got a brochure in the mail from Grand Casino Hinkley about their card system changeover. They have in use the cards with the slotted cards at the Grand Casinos in Hinkley and Mille Lacs in Minnesota, but are switching over to a magnetic strip card system. During the change, they sent everyone a brochure to explain, with a blue round sticker and a red triangular sticker. The blue sticker is to go on the old style cards, and they ask players to stop for a new (magnetic strip) card that will have the red sticker added to it. Then when playing, people are advised to match the sticker with a like sticker on the card reader box on the machine. This way people know which type of card works in which machine.