The Zilla decorative Rock Den is a realistic looking rock formation that features space for basking and climbing, as well as a dark, cool burrowing area to hide and sleep. Each shelter is made with non-porous exterior surfaces that are easy to clean with soapy water. They will not retain water or promote bacteria so terrariums stay healthier and smell fresher longer. Safe for both aquatic and terrestrial environments. Life-Like Texture And Design Heavy Solid Foundation That Stays In Place Non-Porous Exterior Will Not Retain Water, Reducing Possible Bacteria Growth Great For Terrestrial And Aquatic Environments Provides Room To Bask, Climb And Hide