The original holder is designed for Dymo 12mm tape. I have some 24mm tape which needed a home.
2 x 2 → 2x24mm tapes
2 x 3 → 3x24mm + 1x12mm tapes
This was a simple "hack" to the original 12mm, half of the dividers from the standard have been removed allowing for a (slightly non-optimal) 24mm. Doing it properly wouldn't make much difference for the 2x2 2 tape holder, but would allow 4 tapes in the 2x3 holder rather than the 3 x 24mm + 1 x 12mm arrangement.
The author remixed this model.
Hack to remove dividers to allow 24mm dymo tape