Silverback 100 Newton mainspring for SRS & TAC-41 replicas

Silverback 100 Newton mainspring engineered for SRS and TAC-41 airsoft replicas. Built to APS 13 mm standard (9 mm spring guide) with precision performance. Features black coating and laser markings for quick identification. Delivers 100 N force when compressed to 99 mm. Compatible with all TAC-41 models and SRS replicas excluding Push-Bolt mechanism. Essential upgrade for consistent fps and reliability in bolt-action platforms.