The Inserts will fit the Festool Sortainer Sys 4 TL-Sort/3 (Festool 200119). 

Although i haven't tested it, i'm pretty sure they will fit the corresponding Tanos branded Sortainers. 

Please note however, that these insert will ONLY fit the older style sortainers, NOT the newer Sys3 ones. 

I explain how to identify the specific Sortainer this is designed for in the images. 

For whatever reason the manufacturer decided to have uneven spacing between the drawer-sidewalls and dividers. The outer rows are a little wider than the middle one. The middle row also doesn't feature the grid at the bottom. This results in the middle row Inserts (black) not being interchangeable with the outer ones and vice versa.

I designed multiple Inserts with the sizes being 1x1, 2x1, 3x1, 4x1 and 4x4 and an Insert to eclusively fit the middle row.

Feel free to share your opinions and ideas on my work, thank you in advance.

Have fun organizing :)