How to add default values to ion-range with dual knobs

It is possible using ngModel:

html

<ion-range dualKnobs="true" min="4" max="18" step="1" snaps="true" pin="true" [(ngModel)]="knobValues"></ion-range>

ts

private knobValues: Object = {
    upper:4,
    lower:18
  }

From KishuPro