XA-3542-T1-P
Secondary Lock S/A
SAF-Holland

In heavy-duty trailer couplings, a robust secondary locking assembly provides redundant retention to prevent unintended uncoupling under vibration, misalignment, or improper primary lock engagement. This component works in concert with the primary locking mechanism to ensure a positive, two-stage capture of the kingpin within the fifth-wheel cavity, enhancing overall coupling security and towing stability. Engineered for high-cycle operation, the unit features durable materials and precision-fit components designed to withstand the harsh loading and environmental conditions of over-the-road service. Its VMRS code identifies its role within the SAF-Holland locking system family, supporting accurate maintenance planning and part replacement. Within category 42784, this locking subassembly contributes to safety-critical functioning by maintaining engagement even during sharp maneuvers or sudden decelerations. Installation considerations include correct alignment with mating parts and secure mounting to resist parasitic loads. As part of a holistic coupling solution, it reduces wear on primary components and minimizes downtime due to lock-related failures. Safety labeling is standard on the product presentation to ensure awareness of handling precautions during maintenance and service.