Corey is using oxygen. On his mask, he has colored adaptors. Bud is also using oxygen, and his mask has different colored adaptors. Which best describes the devices that Corey and Bud are using?

Corey and Bud are using Venturi masks, but the amount of oxygen they receive is different.
Corey and Bud are using Venturi masks, but the amount of time they receive oxygen is different.
Corey and Bud are using non-rebreather masks, but the amount of oxygen they receive is different.
Corey and Bud are using non-rebreather masks, but the amount of time they receive oxygen is different.