Yealink UH33 Monaural (Single Ear) USB Headset with 3.5mm Compatible with PC/Laptop, Mobile, Tablet & Select Yealink Phones Simple Call Management via Control Unit Integrated LED Indicator and Warning Tone ActiveProtection Technology HD Voice/Wideband Speaker Performance Noise-Cancelling Microphone 330Degree Bendable Boom Arm Compatible Yealink Phones: Supports SIP-T41S /T42S /T46S /T48S /T53 /T53W /T54W /T57W /T58A /VP59 - For T41S/T42S/T46S/T48S: firmware version 82 or higher.