Our petri dishes are available in a variety of sizes and shapes for use in routine procedures and automatic equipmentF. Manufactured from Polystyrene, with excellent optical clarity. The dishes are sterile and each lot is tested to assure uniform quality and sterility. Sterlstar Petri Dishes are designed for the Microbiologist who prefers a heavier dish. The Sterlstar dish offers easy handling, a secure grip, and additional strength.