Durable Material: Spring indexing plunger is made of high quality stainless steel, high hardness, rustproof, sturdy and durable. Easy to Use: Indexing plungers, when in use, pull the handle out and rotate it 90 degrees and release. Lock Spring Screw: Indexing plunger with spring, smooth rotation, solid and durable, long service life. Uses: Self Locking Knob Plunger can control the expansion and contraction of the pin by adjusting the handle, used for indexing, positioning or stop limit. Fine Thread: M10/M12/M16/M20 threads available. Specification: Material: Stainless Steel Size Chart: Overall Length: M10: 51mm/2.01inch M12: 61mm/2.40inch M16: 77mm/3.03inch M20: 90mm/3.54inch Package Includes: 1 x Indexing Plunger Note: Please allow slight variations due to manual measurement and display differences.