AngularJS Material: Material Design component library for AngularJS (1.x). Use angular/material2 channel for Angular Material (v2+).
<span class="break">
<label class="switch">
<input type="checkbox" checked>
<span class="slider round"></span>
</label>
</span><input type="number" name="Density" [(ngModel)]="op.Ro" placeholder="0" required #density="ngModel" [style.width.px]="80">