A car seat configured to be fastened to a vehicle, includes a seat shell and a belt guide disposed at the seat shell to redirect a belt set of the vehicle for rerouting the belt set along a deviation path from an original path. When the belt set is not engaged with the belt guide, the belt set is routed along the original path. When the belt set is engaged with the belt guide, the belt set is routed along the deviation path from the original path. The rerouted belt set improves the symmetry of forces encountered by the vehicle and also improves the kinetics of the car seat during a crash. A break-away feature in the belt guide advantageously absorbs forces at different times during a crash.