Used for very large models in 40k like: Primaris Repulsor, Telemon Heavy Dreadnought, Tyranid Sporocyst, Gigantic Chaos Spawn, Daemon Primarch Magnus the Red, Daemon Primarch Mortarion, Lord of Change, Kairos Fateweaver, and Skarbrand Can also used for Daemon Lords/Princes, Custom jobs, as well as many obscure "Forge World" models.
Used in AoS for: Morathi, Eidolon, Celestant-Prime, Lord Arcanum, and many more