| Size: | 5/8" x 1/2" |
|---|---|
| Connection Type: | Threaded |
| Lead Free: | Yes |
| Thread Type: | Female |
| Material: | Brass |

This looks like it would work if the plastic humidifier hose is 1/4" OD sizing.
No it will not, its a 3/4" thread type.
The picture is incorrect, C74-047 is female thread.
No, the compression end of this fitting is for copper pipe and will not properly seal on pex tubing. Sharkbite part U070LF would be a better choice.