All arms have 2 slits and all down stems have 18 holes in them as well (i think, lol). That bowl really makes it a fast ripper. Couldn't figure out how to get the video rotated, oh well, you get the idea! [ame=http://www.youtube.com/watch?v=pR3ME2ZfxUc]YouTube - Sheldon Black 14in. Beaker w/ 7-arm tree perc, SB Ash Catcher, Ben Wilson Disc Dif Slide[/ame]