Shure HPAQA1 Locking 1/4-Inch Adapter for Shure SRH240A, SRH240, SRH440, SRH550DJ, SRH750DJ, SRH840, SRH940, SRH1440 & SRH1840 Headphones
Replacement adapter for SRH240, SRH440, SRH550DJ, SRH750DJ, SRH840, and SRH940 Professional Headphones. Locking, 1/4", gold-plated.