Stainless Steel Power Hinge Kit - Qty. 2. Engineered to last longer, install easier, and provide greater safety than conventional gate hinges. They are designed for industrial, high-traffic applications with heavy wrought-iron or aluminum gates, Double 5/8 in. Ball bearings for smooth operation, 3/4". Solid stainless steel shaft, grounded and tempered to Rockwell standards, Continuous cycle operation, self-lubricating/no grease fittings.