The box was mixed up on arrival, there were no central fixing screws. Center bolts are over $10 each, so guaranteed lowest price. I should have bought them locally, I think $15 more, but I took my time and wanted them delivered to my door. So I have $85 worth of worthless springs and now I need information on what quality, length and center bolt I need so I can run around town like an idiot to fix this problem.