PowerTRC Liquid Motion Timer (Yellow Pink) | Liquid Bubbler | Ooze Tube Timer | Water Marbles 2 Color Liquid Motion Timer is a great visualization aid to show how water and oil don't mix. It's full of zigzagging Liquid motion fun. Turn this desk toy over and watch the 2 colored liquid drops make their way down the zig zag steps all the way to the bottom Assorted Colors