Bought some a while ago but the runners are just a Z section pressed tin that won't take the weight of anything reasonable other than a stack of paper in the drawers. In all fairness they were bought originally as office drawers, they migrated to the workshop.
Result is they all crash down on one another and then nothing opens.
You can't make new Z runners as the design won't allow any thicker section without leaving a draw out.
I got round mine by building a 18mm plywood shelf / frame assembly were every drawer sits on a plywood shelf and the weight is carried on the bottom.
At least it recycled 24 usable drawers. Mine are now in a 6 wide, 4 hight format.
The old frames went in the metal scrap