4-post lifts for wheel alignment has a hydraulic cylinder is located inside the fixed platform and is thus perfectly protected, High-resistant, galvanised and pre-stretched metal cables,Large-diameter pulleys with self-lubricating and maintenance-free bushes, Automatic mechanical ,back-up safety devices (every 100 mm) with pneumatic release allowing stationary operation with unladen cables and Low-voltage (24V) electrical system with control circuit.