The new THG Medium Reptile Incubation Tray (Cup sold separately) is designed for use with small to medium sized reptile eggs, such as Leopard Gecko, Crested Gecko, Uromastyx, Kings, Corns, Small Pythons, etc. in larger quantities than the Small Tray. Packed with features: Four quadrants to separate different clutches, genetics, etc. Holds several eggs per quadrant. Numbered quadrants for easy egg sorting and record keeping. Easily and neatly stacked for storage. Fits in popular and easily found 128oz Deli Cups. Raised bumps to help keep the egg suspended encourage air circulation. Can be used with a variety of substrates. Water can be added without disturbing the eggs. Super tight fit in 128oz Deli Cup to prevent injury to even the smallest hatchlings. The Reptile Incubation Tray is designed to take advantage of suspended incubation technique minimum egg to surface contact with maximum air circulation around the egg. A 128 oz cup is recommended for best fit, clarity and results (Sold Separately). We recommend NOT using pre-punched cups, 2-4 very small holes punched in the cup are recommended for ventilation. Humidity and ventilation needs for different species vary so we suggest you start with two holes and add as needed. Trays are sold individually, quantity discounts are listed above. A variety of substrates can be used depending on your preferences. Substrate level should be about 1/8" below the bottom of the tray. We have found Vermiculite or water crystals work well for us with 2-4 small holes in the cup. Not recommended for chameleon eggs.