The extensions are 4 cm (1.5 in) high and have a diameter of 3.3 cm (1.2 in). The extensions increase the floor panel 3.3 cm (1.2 in) in height and allow a skirting board to be 15.3 cm (6 in) with a 1 cm (0.4 in) wide skirting board. This product is not compatible with the folding table. This product comes in a pack of two. Materials: Made using powder coated steel with gloss 70. Dimensions: 1.57 H x 1.29 Dia. inches (4 H x 3.3 Dia. centimeters) Care and Maintenance: Please note that wood is a living material and can therefore naturally change its appearance over time, especially when the surface is exposed to direct sunlight. In general: Always wipe the surface with a clean cloth. Use an underlay for hot items and items that risk leaking through moisture. Check occasionally that the mounting bracket and screws are tightened.