Flightless fruit fly culture kit for 20 large cultures. Comes with 2.2 pounds of SuperFly fruit fly media, 20/32 oz fruit fly cups and poly lids, and 1/2 pound of excelsior. Simply add hot water, mix, let cool, add excelsior and flies ((( flies are NOT included )). These cultures will produce hundreds of flies and last up to 6 weeks. Keep at 74-78 degrees for best results.