This fun and innovative infuser is roomy on the inside to get optimum water circulation around the tea leaves and clear glass so you can appreciate the steep as it unfolds.  Angled slits on one side of the base allow the water to flow in and out while the leaves are contained. Treat it with a little care and the Tea Tube will enjoy a lasting place in your kitchen. The thick borosilicate glass is .25 cm thick and the infuser is 6.5" long. We've used it in cups both large and small with solid results.