Two-way Hardhat Mount Headset with Noise-Cancelling Boom Microphone, Black. Ideal for two-way communication in high-noise environments; mounts easily to hardhats with slots, excellent noise reduction of 22dB. Easily replaceable earseals are filled with liquid and foam combination to provide excellent sealing and comfort. 3-foot coiled cord assembly. Requires RKN4097 separate in-line PTT adapter cable for MTX8250, PRO7550, MTX8250LS, MTX850, PRO5550, MTX850LS, MTX950, MTX9250, HT750, PRO5150, HT1250, PRO7150, HT1250LS, HT1250LS+, HT1550. Hardhat not included.