Pan is constructed of high-density polyethylene for years of continued use. Designed for grades 4–10 where students are involved with routine dissections using earthworms, crayfish, clams, grasshoppers, sea stars (starfish), perch, and grass frogs. Outside dimensions 10 in. x 7 in.Less expensive than aluminumWon’t rust, crack, or leakNonskid pads prevent movement on tableBottom retains shape - does not become rounded with useNot as deep — easy to perform routine dissectionsChemical resistantStackable for storageDesigned to be used with 10 in. x 7 in. Flex-Pad only (included), not with wax