Thanks for your comment. The video explains pretty well. To add to it, this is the only standardized polycarbonate lid currently available that: - Accounts for all types of Auto Feeders possible - Accounts for all types of Light Mounts possible - Has an individually accessible Overflow Box without moving the lid - Has additional overflow support to hold over 80 lbs on top while not bowing into the water - Has a minimal framing design with less than 1" of framing material, to minimize condensation and salt creep, thus minimizing normal maintenance - Requires no measurements of the tank, overflow, or light spacing on the back panel - Comes 5 year warrantied against all bowing, hazing, crazing, yellowing, etc within normal use (see our Warranty Policy) Additionally, the Standard Lid for the Waterbox Marine X 110.4 is less than 400 shipped on our website to anywhere within the Continental US. Hope this is helpful.