Calliphora (or calliphoridae) larvae. Ideal for GCSE biology animal behaviour investigations using a choice chamber or maze. (Spoiler: maggots don't like light!)
Maggots supplied are at the last stage before pupation. Keep refrigerated to slow down the time it takes for the maggot to pupate.
Once you have finished your investigations using the blowflies it is best to kill them by freezing for a few days before disposing of.