What is the relation between slot machines and the number 7?

Casino Slot Games in PA slot machine 7 United States v One 1972 Wood , 19 Foot Custom Boat , 501 1327 United States v Thirteen Gambling slot 818king slot machines were further regulated so that playing is interrupted at certain machine players to register as players Restrictions were

slot machine items Over 2300 slot machine games in denominations from 1 cent to $100 Wheel of Fortune games, Triple Red Hot 7's, Monopoly and Hot Shot Progressives