Atdec AWM-P40X-B 400mm Stackable Monitor Mount Post in BlackAtdec AWM P40X B 400mm Stackable Monitor Mount Post in Black The Atdec AWM P40X B is a revolutionary stackable 400mm (15. 75") monitor mount post designed for enterprise workspaces that demand flexibility and efficiency. Part of the Atdec Modular family, this black finish post can be stacked to double its height to 800mm (31. 5") using the AWM X40 adaptor kit, enabling fast upgrades to two layers of monitors without disassembly or removing displays.