How is the system different from using the pump by itself?

The MiniMed™ 770G system, sometimes referred to as a hybrid closed loop system, automatically adjusts* delivery of basal (background) insulin based on CGM readings. This means that the pump gets glucose readings from the Guardian^™ Sensor 3 and transmitter automatically, and then gives you more or less insulin based on your real-time needs. Having a pump and a CGM that speak to one another can help reduce both high and low glucose levels^1,2.

*Refers to SmartGuard^™ Auto Mode. Some user interaction required. Individual results may vary.

https://www.medtronic-diabetes.com.au/mm780g-supported-devices