with a low-wattage lightbar between the headlamps; the lightbar became a design feature later adapted by the Mercury Topaz and Tracer (and other automakers in the early 1990s). The lightbar design element largely emphasized the lack of a conventional grille (while primarily a "bottom-breather" design, a vestigial air intake slot was also designed into the bumper below the lightbar); a design pioneered by the 1950s Citroën DS, within Ford, the configuration was also used by the Ford Mustang SVO and Ford Sierra. As with its Marquis predecessor, the Sable station wagon was designed with a rear liftback, but introduced a new configuration for the rear hatch, allowing the rear window glass to be opened separately from the rest of the rear hatch. In a design first for Mercury station wagons, exterior woodgrain trim was not offered as an option. Alongside the Taurus, the Sable was the first American-produced sedan to use aerodynamic composite headlights with replaceable halogen bulbs; to begin their use, Ford (and other auto manufacturers) lobbied the National Highway Traffic Safety Administration (NHTSA) to have them approved, with the 1984 Continental Mark VII becoming the first American car to use them. While the Sable shared largely the same interior features as the Taurus, in a departure from tradition, the Sable was designed with a model-specific dashboard (partly integrated into the door panels). Sable sedans were equipped with a 50/50 split bench seat as standard equipment (joining the Grand Marquis as a six-passenger Mercury sedan); as an option, front bucket seats were offered (reducing capacity to five). The Sable wagon was offered with an optional rear-facing third-row seat, bringing seating to seven or eight; for the first time since the 1977 Cougar wagon, Mercury offered the design in its midsize station wagon. During its production, the first-generation Sable underwent few changes. For 1989, the exterior underwent a mid-cycle revision; the amber parking lamp lenses were replaced by clear units and sedans saw revisions to taillamp lenses. For 1990, the Sable underwent a redesign of the dashboard to accommodate the addition of a driver-side airbag; a CD player was added as an option. Trim The first-generation Mercury Sable was sold in two trim levels (opposed to the four of the Taurus). In line with other Mercury models, a base-trim GS (comparable to the GL-trim Taurus) and top-trim LS (slightly above the Taurus LX) was offered. As Mercury never offered the