The 24-inch iMac comes with a built-in stand. You can remove this stand and add a VESA mount adapter to use the iMac with VESA-compliant mounts. VESA-compliant mounts are the industry-standard mounts for electronics equipment such as HDTVs and computer monitors. The VESA Mount Adapter Kit includes the tools you need to remove the stand from a 24-inch iMac. Writer Bio

How to Remove the Stand From a 24 Inch iMac - 67