An implant with an adjustable height for spacing apart skeletal structures. The implant includes a base with a hollow interior. Collars include threaded inner surfaces and are positioned within the hollow interior of the base and are rotatable relative to the base. Threaded posts extend outward from the base and are threaded into the collars. Rotation of the collars adjusts an amount that the threaded posts extend outward from the base. An overall height of the implant can be adjusted to accommodate the size of the space and for the posts to contact against and space apart the skeletal structures.