htmlAttr.erb

//HTML
<% products.each do |product| %>
<div class="product" data-id="<%= product.id %>">
  <%= link_to_image product.thumbnail, product %>
  <%= product.name %>
  ...
</div>
<% end %>


//JS
$('.div.product').click(showScreenshots)
showScreenshots = function(){
  selectedProductId = this.dataset.id
  //load the screenshots for the product with id = selectedProductId
}