A team of Florida attorneys have launched a putative class action lawsuit against Mercedes-Benz USA LLC, its German manufacturer Daimler AG and headrest manufacturer Grammer AG, claiming there’s a dangerous defect in hundreds of thousands of cars.

The Neck-Pro active head restraint is designed to help Mercedes-Benz drivers avoid whiplash in a crash by springing forward to cradle their head. But the complaint claims those restraints can be dangerously trigger-happy, capable of deploying unexpectedly.