Need to repair or replace the locking mechanism on your Louisville extension ladder? This PK100A Runglock Kit is designed just for that. It's a replacement safety kit specifically for Louisville ladders with round rungs (the 'FG' in the name likely stands for FiberGlass). The Runglock is the part that clicks onto each rung to secure the two ladder sections at your desired height. Keeping these parts in good working order is crucial for safe ladder use. The kit comes with everything you need for one repair. The package dimensions are about 10\L x 7.6\W x 1.5\H, and it's made in Mexico. Always prioritize safety – if your ladder's locks are worn or broken, this kit can help restore its secure operation. Please confirm this is the correct kit for your specific Louisville ladder model before ordering.