This range covers Kia, Mazda, Nissan and Volvo applications, matched by OEM part number rather than by dimensions alone.
Two bolts can share a thread and differ completely in what they are designed to do. Torque-to-yield bolts stretch when tightened and must not be reused; flange bolts spread load over a wider area; studs locate a part before it is fastened. Using the wrong one is a common cause of a joint that comes loose or a gasket that leaks again within a few thousand miles.
Replace bolts whenever the specification calls for new ones, when the head or thread is damaged, when the bolt has stretched (it will no longer run down by hand), or when corrosion has reduced the section. Clean the threads in the hole before fitting a new bolt, since debris stops it reaching the correct torque.
Listings give the size, the years and the OEM number, and note where a bolt is a specific grade or a stretch type.
