timepicker-toggle.html

<button
  matIconButton
  type="button"
  aria-haspopup="listbox"
  [attr.aria-label]="getAriaLabel()"
  [attr.aria-labelledby]="ariaLabelledby()"
  [attr.aria-expanded]="timepicker().isOpen()"
  [tabIndex]="_isDisabled() ? -1 : tabIndex()"
  [disabled]="_isDisabled()"
  [disableRipple]="disableRipple()">

  <ng-content select="[matTimepickerToggleIcon]">
    <svg
      class="mat-timepicker-toggle-default-icon"
      height="24px"
      width="24px"
      viewBox="0 -960 960 960"
      fill="currentColor"
      focusable="false"
      aria-hidden="true">
      <path d="m612-292 56-56-148-148v-184h-80v216l172 172ZM480-80q-83 0-156-31.5T197-197q-54-54-85.5-127T80-480q0-83 31.5-156T197-763q54-54 127-85.5T480-880q83 0 156 31.5T763-763q54 54 85.5 127T880-480q0 83-31.5 156T763-197q-54 54-127 85.5T480-80Zm0-400Zm0 320q133 0 226.5-93.5T800-480q0-133-93.5-226.5T480-800q-133 0-226.5 93.5T160-480q0 133 93.5 226.5T480-160Z"/>
    </svg>
  </ng-content>
</button>