Aquascape Fountain Shims are ideal for leveling a wide variety of water features and fountains including resin, concrete, and GFRC features. Durable plastic construction makes these shims impervious to water damage and allows the shims to be stacked when necessary. Shims measure 4-1/2 inches by 3/4-inch. Six easy-to-use shims included. Aquascape is passionate about the products we produce, providing unique products, designs, and features that stand above the competition.