Within the Drive Gate Base Costs page there are several options determining the applications.
Option #1 are those overall opening widths that are 12′ or less, requiring no steel frames. An approximate weight per gate of 125 lbs. Created with a system of joints that prevents these gates from ever sagging. Mounting to wood 6×6 posts with the same stainless steel, black ball-bearing hinges as the pedestrian gates, or to wood jambs that are in turn mounted to masonry columns.
Option #2 are those with overall widths beyond 12′ and requiring a steel frame that is visible and exposed from the property side, to which the wood gates mount against. Although on rare occasions we’ll provide the steel frame, the vast majority of sites find it more efficient for the steel frames to be fabricated by their local automation contractor, who does this according to our drawings to insure such frame aligns with the gate’s rails and stiles. These gates typically weigh about 200 lbs each and require either steel 6×6 posts or masonry columns with steel cores.
Option #3 is equipped with an invisible steel frame embedded within the gate construction itself for a gate net thickness of 3″. A vastly more complex procedure with the advantage of eliminating the exposed steel. Typically weighing about 250 lbs each.
Option #4 is for sliding gates, all of which require steel frames. Normally a single frame spanning the opening, onto which the pair of gates mount and operate as a single-gate sliding function.
All of this discussed in detail in the two links above.