Can get the ID of the field like field_560389746a525. I have a The_field thats called companies that repeat
<div class="header_text">
<p>
<? the_field('company_headertext');?>
</p>
</div>
<section class="container-fluid colorbg">
<div class="rowcarousel">
<?php
if( have_rows('companies') ):
while ( have_rows('companies') ) : the_row();
?>
<div class="plaatje<? the_sub_field('company_id');?>">
<a href="<?= the_sub_field('company_link');?>">
<img class="companyimg" alt="<?= the_sub_field('company_title');?>" src="<?= the_sub_field('company_image');?>">
</div>
</a>
<?php
endwhile;
?>
<?php
endif;
?>
</div>
</div>
</section>