Answer
Feb 21, 2017 - 12:00 AM
Thank you for your inquiry. The on center measurement is when you measure from half way through one slot to half way through the next slot. You can measure up or down to the next slot. This should measure to 3" for the accessories to work with the panels we provide or for the accessories to work with any existing panels. Please let us know if you require additional assistance. Thank you again, have a great day!
