DoubleSight Flex Stand Extension Post: * Replaces the standard base and allows the stand to be installed into the center post of another stand creating a stacked monitor array * Configure an array of up to 9 monitors on a single footprint with any combination of DoubleSight Single, Dual, Triple or Quad Multi Monitor Flex Stands * Compatible Flex Stands include: DS-130STA, DS-219STB, DS-224STA, DS-230STA, DS-319STA, DS-322STA, DS-330STA, DS-424STA, DS-430STA and DS-1900WA, DS-2200WA, DS-2200WAC Dual Monitors