Glycine - an amino acid that decreases the amount of time it takes you to fall asleep and promotes more restful sleep.
Magnesium – a mineral that  plays an important role in sleep regulation; it helps your body relax and can improve symptoms of insomnia (Source).
Melatonin - a natural hormone that helps regulate your circadian rhythm and synchronize your sleep-wake cycle (Source).
This dosage was designed to better mimic your body’s natural needs, instead of providing an unnecessary megadose, as is common in many over-the-counter sleep aids.