21010000009 CONN. MICRO JACK ACCES.LOCKNUT M20 21010000009 is a premium microphone jack accessory that featuring a Locknut type made of Plastic material. Designed in M20 shell size, available in nan color. Manufactured by HARTING in the Harax® series. Compliant with ROHS standards and available in BULK packaging. Perfect for enhancing connectivity and durability in professional audio systems.