Prestone AS661 Engine Block Stop Leak with Kevlar, 16.5 fl. oz.
- Triple seal protection made with DuPont Kevlar.
- Stops cooling system leaks fast without blocking or corroding the cooling system.
- Designed to seek out and seal leaks when added to any color of antifreeze/coolant.
- Affordably fix engine block leaks and avoid expensive engine repairs.
- Latest evolution from the leader in cooling system products.