Ubercart Attribute. Limit number of checkboxes that can be ticked

Drupal 7 Ubercart 7.x-3.8 I have a product in Ubercart. It is a box that can contain 6 bars of soap. I have set up an attribute with check boxes that shows 10 types of soap and I want to be able to limit the user to selecting 6 of those check boxes. Is this possible?