Beginning in the late 1990s, ProSlide began manufactures four kinds of Bowls: ProBowls, CannonBOWLS, BulletBOWLS, and BehemothBOWLS, all four types consist of an enclosed flume that terminates in a bowl; riders travel in a spiral around the bowl (using centrifugal force to stay on the bowl's wall initially) before dropping into a splashdown pool. ProBowls are enclosed body flumes which end in a bowl with an open top. CannonBowls and the larger BehemothBowls accommodate 2- and 4-person inner tubes, and have a common exit in their centers.