D66 STUD GRADE ADHESIVE. A fast curing, high strength anaerobic threadlocking compound for bonding and sealing threads and retaining cylindrical parts in general industrial and automotive applications. Ideal for use on fasteners up to 1ÉÉ (25mm) in diameter, providing permanent locking and eliminating the need for Èdouble nuttingÉ. Ideal for use with transmission and engine blocks in automotive applications.