This is what makes it go. Without polyester catalyst, polyester resin would never harden. (well, almost never) We provide you with the appropriate amount for any quantity of resin you might buy, but if you need additional material because you're in
a hurry, or maybe it's a little cold where you are working, we can sell you that too.
Special Shipping Notes: This product is classified as "Restricted" by the DOT. This means that this product can only be shipped via UPS Ground Service. TIP: If you are ordering other items that need to be shipped via a faster service, consider placing all "Restricted" items on one order and all other items on another order with faster shipping.