Your seat belt is in the wrong place. Everybody’s is, but supplier ZF said it can help.

At issue: comfort vs. convenience. The best place to put the buckle so it’s easy to reach is not the best place for the belt to hold occupants secure in a crash.

The answer: ZF’s Active Buckle Lifter. It raises the buckle 2 to 3 inches so it’s easy to find, then retracts when the belt clicks in.

Lowering the point where a belt is latched to the seat frame helps assure the belt is across the occupant’s hip bones, not higher on the torso, said ZF seat belt specialist Ed Schlaps.

That prevents submarining, when a person slides under the seat belt and into the dashboard or seat back in front of them during a crash. Submarining can lead to serious leg injuries and can reduce air bag effectiveness.

The system’s not cheap. ZF won’t say how much it costs, but the only vehicle that uses it today is the Mercedes S-class, which starts at $91,250.

The S-class has the buckle lifter in the rear seat, where, in addition to lifting the buckles to make them easy to find, it pulls them down into the seat cushions when they’re not being used.

Mercedes asked for that feature because China is a huge market for the S-class, so the car is frequently driven by chauffeurs and the rear seat is almost always occupied.

“Mercedes wanted the buckle out of the way when not in use, but still easy to buckle,” Schlaps said.

ZF has had development programs with several automakers for North American vehicles, but none made it to production so far.

ZF is also experimenting with electric retractors that can give the driver warnings as well as tightening in high-G maneuvers that could indicate a crash is coming.

Called ACRs, or active control retractors, the belts can tug on the driver if the car wanders out of its lane or starts to merge into another vehicle. They can also tighten in response to autonomous emergency braking, before the brakes are applied.

In demo vehicles, the system is like having a back-seat driver tap you on the shoulder, but slightly less annoying. Like other good driver alert systems, response quickly becomes reflexive.