Expandable fusion device and method of installation thereof

An apparatus comprising:

• a central ramp for an intervertebral implant, the central ramp comprising:
• a first expansion portion at a first end of the central ramp, the first expansion portion comprising a first side portion and a second side portion, the first side portion comprising overlapping ramped portions, and a second side portion comprising overlapping ramped portions;
• an extension that extends from the first expansion portion to a second end of the central ramp;
• a second expansion portion, the second expansion portion extending from the extension between the first end and the second end of the central ramp, wherein the second expansion portion comprises a first ramped surface and a second ramped surface;
• wherein the first expansion portion and the second expansion portion are non-moveable relative to one another as part of a single body;
• a driving ramp, the driving ramp comprising a through bore, an upper side, a lower side, a first side portion, connecting the upper side and the lower side, and a second side portion connecting the upper side and the lower side, the first and second side portions each comprising a ramped surface facing the central ramp, wherein an extension of an actuator assembly extends through the through bore of the driving ramp;
• and
• a first end plate and a second endplate, wherein the first endplate is in the engagement with the central ramp and the driving ramp, wherein the second endplate is in engagement with the central ramp and the driving ramp.