Johnson Marines' locking nuts and locking rings come in a variety of thread sizes, thread counts, and rotations. They are used for different purposes and work with different Johnson model numbers and series.
This is a replacement for a Knurled Nut for a turnbuckle with a 1/4 in. (6mm) thread, 28 thread count, and a right hand rotation. It is compatible with the JH24302/12 series.