HPAQA1 on August 20, 2015 | Marketing Team Threaded 1/4" Adapter Threaded 1/4" gold-plated adapter for SRH240A, SRH240, SRH440, SRH550DJ, SRH750DJ, SRH840, SRH940, SRH1440, SRH1540, and SRH1840 Professional Headphones.