- Joico K-Pak Reconstruct Split End Mender seals and prevents split ends. This featherweight formula mends split ends while protecting hair to prevent future damage. Especially designed for damaged or chemically treated hair; mends existing split ends and prevent new ones from forming. Features an exclusive dual-polymer technology that deeply penetrates porous hair ends to create an ultra durable bond. Also contains a combination of K-PAK technologies—Quadramine Complex®, Keratin Silicone Complex and Hair Protection System—ensures maximum protection and reconstruction from the cortex, locks in moisture, seals the cuticle, and delivers smoothness to the hair. Apply to towel-dried hair, concentrating on ends, and style as usual.