Modgy products are constructed of BPA-free plastic materials, making them expandable, shatterproof and recyclable! Modgy is committed to reducing their impact on the environment, and protecting Mother Earth is important to their company. Modgy uses recycled products where possible in their business processes and technology to lower energy usage. Modgy products are created from durable, thin layers of PET, PA and LDPE. The vases and luminaries expand with water. When you're done using them simply empty, collapse and store until next time.