Majestic Polyguard Airseal Infant Vault is the ideal protection for an urn with keepsakes. It includes a dome with base, and a roll of mastic sealant to be used for a permanent seal. These high-density polymer vaults are an economical alternative to concrete grave liners while providing a water-resistant environment for the contents. This product has a 100-year warranty. It is completely non-biodegradable. It offers a double seal. It has a special mastic sealant for a permanent seal. This vault offers ultimate protection while preserving cemetery aesthetics. The majestic infant vault is designed to nicely fit the standard 2"6", 3'6", 4" 6" metal or wood casket or urn plus keepsakes. Mastic sealant is used for a permanent seal, the result will bring protection, permanence, and peace of mind to a grieving family. The dome with a base design is structurally strong, impervious to water and soil acid. When the mastic sea The inside narrow measures: 22" W X 48" L X 15" H. The inside wide Measures: 25" W X 52" L X 20" H. Large Outside measures: 31" W X 57" L X 22" H.