STAKOOL 390, White acrylic sealant flexible roof patch is an extra tough, flexible repair compound designed to patch splits, cracks and holes in roof surfaces This waterbased patch dries quickly to a nontacky surface which offers great adhesion to all coatings applied over it It is designed to repair cracks and holes up to 1 in width STAKOOL 390 should be used with universal patching fabric STAKOOL 390 remains flexible while it expands and contracts with your repair, making it ideal to use with all STAKOOL products