We also have a sand saver that consists of a 3 ½ x 3 ½ solid square plastic material with a beveled top on both sides. This sand saver will fit into free stalls, providing a continuous system. The sand saver will come inter locked with a flat surface on the bottom to mount onto concrete. It's easy to drill thought and mount to the curb. The sand saver will save a lot of sand from going into the lagoon system. We have the most durable sand saver on the market today! Call for more information. We also have curtain protectors.