Material: Stainless steel Threaded sleeve 1.4305 Indexing pin 1.4305 Mushroom knob black grey thermoplastic. Version: Indexing pin not hardened, ground and bright. Note: Indexing plungers are used to prevent any change in locking position due to lateral forces. A new locking position can only be set after the pin has been manually disengaged. A washer is available to aid by screwing in the indexing plungers. The washer slides beneath the mushroom knob so that the carrier pins engage in the slot.