Yealink SIP-T20P, SIP-T22P, SIP-T26P, SIP-T28P. Cisco 7902, 7905, 7905G, 7906G, 7910, 7911, 7912. This HW121N Binaural Noise-Canceling Headset with U10P-S QD Cable is NOT compatible with Cisco 6921, 6941, 7940, 7960, 7970, 8941, 9951 IP Phones.
eBay