Creative Labs Tactic3D Sigma. Device connectivity: Wired. Ear coupling: circumaural, Headphone frequency: 20 - 20000 Hz, Impedance: 32 Ом. Microphone frequency: 80 - 14000 Hz, Microphone sensitivity: -41 dB. Mac operating systems supported: Mac OS X 10.5 Leopard, Mac OS X 10.6 Snow Leopard, Mac OS X 10.7 Lion. Minimum RAM: 512 MB, Minimum processor: Pentium 4 1.6GHz