|20 line online slot machine is a very popular kind of slot game that is available in the portfolio of Microgaming, RTG, Playtech, Rival, 888, Chartwell, Cryptlogic, WagerWorks, BossMedia, TopGame companies. This type of online slots usually has vivid graphics, nice sounds and, of course, interesting bonus features. They are not limited just to free spins. It can be gamble feature as well or some unique game with totally different interface and gameplay. Besides there are a lot of 20 line slot games offering progressive jackpots. It can add more attractiveness to the game as any time you can become the owner of huge wealth or a little bit smaller one :-).