Stackable spool stand

My version of spool storage Units of 2 spool slots can be stacked vertically. Stacks can be connected to make them more stable. Inner width of a spool slot is 75mm.No support is needed.Items clip together with just a bit of force. No glue is needed. Number of elements needed for 1 stack3 side elements per unit8 top-bottom crosspiece items (4 top, 4 bottom)4 middle crosspiece items for each additional unit stacked. Assembly of 1 stack Place 3 side elements onto 4 top-bottom crosspieces. Place 4 m