Our suction bowls adhere best to smooth, non-porous surfaces such as plastic, tile, glass, fibreglass or metal. High chairs or wooden surfaces that are textured, porous or have slight curves will make it difficult to achieve lasting suction power. As the Tripp Trapp has a slightly textured surface unfortunately this will affect the suction power of our bowls and plates and will therefore result in you having to possibly re-suction during mealtimes.