Kaithe Summons can be equipped in a player's Gear menu, and can be used in Landscapes (Plains of Eidolon, Orb Vallis, and Cambion Drift). When activated, the player will immediately auto-mount their Kaithe. Players can activate the Kaithe Summon even while in mid-air. It has infinite uses.
While on the Kaithe, only secondary weapons can be used. The Kaithe specific abilities Hoof Stomp and Steadfast Dismount can be used by the Warframe.
Operators, and by extension the Origin System's Drifter, cannot use the Kaithe Summon.