Rannsgeer UV340R-H4P Dual Earhook Headset Microphone is designed especially for Audio Technica Microphone System. The ultimate in low profile, high performance vocal pickup Omnidirectional condenser headset microphone. The Headset frame is adjustable by sliding to the top frame, inward or outward, for large or small size head. Plus, the microphone boom is replaceable to the right or left side of the headset frame as per user desire. Product Features include Sweat and Dust-Proof Made Primarily for Indoor and Outdoor activities. Can be used for on Stage, Houses of Worship, School Lecturers and Other Applications that Require hands-free Operation Ultra-Light Weight, Easy Clip-on Style Compatible with Audio Technica Body-Pack Transmitter Models: ATW-T210, ATW-T310, ATW-T75, A TW-T701, ATW-110G, ATW-T1000. This headset not compatible with Audio-Technica Transmitters: T35, T75, T211, T601, T701, 1000 Series, 1200 Series, 3000 Series, 4000 Series, 5000 Series, 7000 Series. RoHs and REACH Complied. Without Pb, Hg, Cd, Cr6, PBB, PBDE.RoHs and REACH Complied. Without Pb, Hg, Cd, Cr6 , PBB, PBDE. Sweat and Dust-Proof Made Primarily for Indoor and Outdoor activities. Suitable used for on Stage, Houses of Worship, School Lecturers and Other Applications that Require Minimum Microphone Visibility with hand-free Operation. The Headset frame is adjustable by sliding to the top frame, inward or outward, for large or small size head. Plus, the microphone boom is replaceable to the right or left side of the headset frame as per user desire. Not Compatible with Audio-Technica Transmitters: T35, T75, T211, T601, T701, 1000 Series, 1200 Series, 3000 Series, 4000 Series, 5000 Series, 7000 Series. This replacement ear-hook headset does compatible with Audio Technica Body-Pack Transmitter Models: ATW-T210, ATW-T310, ATW-T75, A TW-T701, ATW-110G, ATW-T1000.