VerticalTabsKit

// Create VerticalTabsKit.
$tabs = $k->verticalTabs();

// Create a "dogs" TabKit & add it to the VerticalTabsKit instance.
$dogsTab = $tabs->createTab('dogs')
  ->setTitle($this->t('Dogs'));
$dogsTab->append(
  $k->image('dogs_image')
    ->setTitle($this->t('Image'))
);
$dogsTab->append(
  $k->textarea('dogs_description')
    ->setTitle($this->t('Description'))
);
$dogsTab->append(
  $k->checkboxes('dogs_attributes')
    ->setTitle($this->t('Attributes'))
    ->appendOption(['a' => $this->t('A')])
    ->appendOption(['b' => $this->t('B')])
    ->appendOption(['c' => $this->t('C')])
    ->setDefaultValue(['b'])
);

// Create a "cats" TabKit & add it to the VerticalTabsKit instance.
$tabs->createTab('cats')
  ->setTitle($this->t('Cats'))
  ->append($k->image('cats_image')->setTitle($this->t('Image')))
  ->append($k->textarea('cats_description')->setTitle($this->t('Description')));