MICROSEAL offers an easy, economic, one-step solution for sealing porous castings, welds, coatings and leaky joints. It also secures loose screws and nuts and prevents rust. Works great for boats with leaky water tanks too!


Please note: Due to COVID-19, Microseal is presently on very limited hours of availability. You may email microseal@microleak.com or call us with your contact information and we will get back to you as soon as possible. We apologize for the inconvenience.


Microseal is a plastic in thin liquid form with unusually high capillary action. It fills fine pores, micro-cracks and joints between fitting parts, then hardens into a pressure-tight seal.Application is easy; just dip, brush or spray. The seal dries in about a minute and hardens at room temperature. Large castings can be spot sealed.

Our product line includes Microseal-AC, Microseal-MEK, and Miniseal in 1-gallon and 5-gallon sizes. We accept most credit cards and ship within the United States and internationally to Canada and Mexico.

Place your order today!

  • Minimizes leaking, porous rejects.
  • Inexpensive — a little sealant goes a long way and it’s easily applied.
  • Allows for less expensive foundry and manufacturing techniques.
  • Eliminates the need for pressure testing.
Have a leaky boat tank? Keep the water on the inside of that tank! Use Microseal to seal it!boat