2.5mm Call Center Headset for Polycom SoundPoint Pro SE 220, 225 and IP 321, 331 Corded Call Center headset with Noise cancelation, Acoustic Shock Protection and RF-Shield Compatible with Cisco Small Business SPA500 Series IP Phone: SPA303, SPA501G, SPA502G, SPA504G, SPA508G, SPA509G, SPA512G, SPA514G, SPA525G2; Polycom SoundPoint IP 321, 331, 331c, SoundPoint Pro SE-220, SE-225 Rotatable, Flexible Long-lasting metal microphone boom, Adjustable head-band 2.5mm Quick Disconnect Cord Directly plug into telephone headset jack, no need amplifier Clear sound, durable, 5ft cord, Lightweight, Over-the-Head style, Soft Leatherette Ear Cushion. Rotatable, Flexible Long-lasting metal microphone boom, Adjustable head-band. Rotatable, Flexible Long-lasting metal microphone boom, Adjustable head-band. 2 Years Manufacture Warranty Included!