The Curio collection is inspired by classic, mid-century design and is made entirely of sustainable, furniture-quality, pre-finished europly, rather than MDF or particleboard. Handcrafted in the United States, there are three styles of CURIOs available: Maple, Walnut and Patterned Walnut. The liner is custom-made to fit perfectly inside the CURIO litter box and is constructed from durable 1/8-inch ABS polymer. It is 100-percent waterproof and its 10-inch-high walls provide maximum litter retention. The convenient handles make it easy to lift out when it is time to replace the litter.