Quality Material: These clear petri dishes are made of high-quality plastic, featuring a smooth surface and highly transparent body, suitable for most experiments and providing you with a great user experience. Suitable Size: The outer diameter including the lid is 90mm/3.54 inches, the depth is 15mm/0.59 inches, the plastic thickness is 0.6mm, and the lid's diameter is slightly larger than the plate for good air circulation. Sufficient Quantity: You will receive 20 plastic petri dishes with lids, a sufficient quantity to meet your various needs and replacements. Plus, you can share them with your partners or classmates. Wide Range of Uses: You can use these project petri dishes to help children with their science experiments, related theme parties, art projects, and so on. You can also use these plastic petri dishes as gift boxes to store nice presents. Thoughtful Design: These school petri dishes are optically clear for good clarity during microscopic examination. The petri dishes have a flat growth surface for uniform cell growth without clumping, and vents in the lid provide constant gas exchange. 20 Pcs 90 x 15 mm Plastic Petri Dishes with Lids, Clear Project Petri Dishes for Labs, Storage, School Parties