IKEA SAMLA Rail Mount

These rails can be mounted under a shelf to use IKEA Boxes as a drawer.
The Part "Schiene IKEA Box Mitte V2" can be used if you want to mount two boxes next to each other at one rail.

There is one solid version and another version with less material on the sides of the rail.

I tested the solid rail with the small SAMLA Box 5l 28x19x14. Mounted them under a shelf on the long side of the box and the box slides perfectly between the rails. I am expecting the same for the version with less ma