Digital post house Post Office approached NotCom to do this demo using practical modelmaking and special-effects. Viz made the model and provided the special effects and rigging.

We made this product demo using entirely analogue models and special-effects. The first step is to make the model tea bag at 200%, which you can see here. In the bottom of the model is an invisible opening to put in and take out tea. This is nescessary because the tea swells in water giving the impression that the tea bag is over-filled. Later we tested the shot in our own studio using the Casio high-speed camera. It was clear that the model worked but that we had to imrove the movement of the tea. By injecting a jet of water into the tea bag we could make the tea swhirl in the tea bag and at the same time avoid the accumulation of tea in the top of the bag. Without testing this would have caused major delays on the film set.