For BMW G Series 356 Series X3X4X5X6X7 Original Seat Belt Pre Tightening System (4GQ) New Original Three color seat belt

The BMW seat belt pre tightening function is an important component of the vehicle’s active safety system, aimed at quickly tightening the seat belt before or immediately after a collision occurs, reducing passenger displacement, and improving protection effectiveness.
Features
Automatic triggering: When the vehicle speed exceeds 18 km/h, the system will automatically tighten the seat belt according to the passenger’s body shape, eliminating slack gaps
Quick response: When a collision or sudden deceleration (such as acceleration ≥ 0.5g) is detected, the system can tighten the seat belt webbing 50-100 mm within approximately 0.1 seconds
Collaborative work: usually deployed before the airbag (about 0.05 seconds in advance), to secure the passenger in the optimal position and ensure that the airbag effectively functions
Force limiting protection: equipped with a tension limiter, when the seat belt tension exceeds the preset value (such as 4 kN), the webbing will be moderately released to avoid excessive compression on the chest