The rock is made from insulated material that does not absorb water. One piece, no seems, no internal insulation and ideal for continuous use in extreme environments. The radius corners and soft beveled bottom make it easier to eat from and easier to clean. Trays stack easily. Manufactured with an FDA approved material and built to ISO quality standards. These trays retail for $78.99 each. 1.77" H x 14.25 W x 9.5" D. This listing is for 8 trays.