A flat top machine at a casino is one in which the maximum win is limited to a certain amount. Let’s say, for example, that you are playing a slot machine that has a maximum jackpot of 5000xs your bet. It doesn’t matter how many players are engaged in this machine online, the jackpot will stay the same no matter what. Flat top machines can also come in the classic variation as well. Thus, if you are playing the above mentioned slot, the minimum bet will yield you a win of $500, whereas the max bet will garner you $1 million.