Kendall Howard has made a slight design Change the Modular Wallmount Racks. The rails are now attached with Rivets. This will reduce Installation time, and make it easy for people to use. Now just take it out of the box and hang the sides on the wall with the attached Template and install components. This Change will not effect functionally or strength. It will provide the same 19” or 23” compliant mounting system and increase customer satisfaction Kendall Howard Part Number Effected by Design Change. 1915-3-001-08 8U Wallmount Rack 1915-3-001-12 12U Wallmount Rack Please contact your account Manager if you have any questions,