Standard 1pin 3.5mm plug audio jacks; with electroplating anti-oxidation design to avoid the poor contact situation Big Ear Hook ergonomic design; Comfortable wearing for long time; Fit either the left or right ear Clear sound quality; Long service life With short cord so it won't be wrapped around inside your shirt; durable PU material; good resilience, long enough for your daily work Fits two-way radios (audio only), radio speaker mics, remote mics, MP3 players, and other audio accessories with 3.5mm earphone jack Works great for security, police, law enforcement or any other hearing needs in noisy enviroments Note:Please confirm the Audio Jacks type your device need(3.5mm)