This is a high - quality Kadee knuckle spring designed for standard - head couplers in HO scale. These metal knuckle springs fit most Kadee HO couplers, excluding #58, #78, #119, #150 - Series, #178, #711, #714, and #2100. Each package contains one dozen springs, providing you with enough spares for your model train setup.

Using these Kadee knuckle springs is easy. Just replace the old or damaged springs in your standard - head HO scale couplers. Make sure to align the spring properly for smooth operation. When handling the springs, be careful as they are small and can be easily lost. For maintenance, keep them in a dry place to prevent rusting. If you notice any signs of wear, it's a good idea to replace the spring right away to keep your couplers working well.