Greelan Technology is one of the leading China rj11 headset manufacturers and suppliers, and also a professional factory and company, welcome to wholesale and buy cheap and high quality school education rj11 headphone products for English learning and check the price with us. RJ11 Language Lab Headset Language Laboratory Headset Features: 1)Headphones: a)  Frequency Response: 125Hz ~ 8000 Hz, ± 17 dB (0dB = 20uPa The) (input power = 1mW); b)  Electrical Impedance: 32Ù ± 20%; c)  The characteristics of sound pressure level (sensitivity): the ≥ 100dB/1mW (0dB = 20uPa). 2)Microphone: a) Frequency response :40-20000HZ b) Type: electrets microphone; c) Receiving voltage response: -47 ± 2 dB (0 dB = 1V/Pa); d) Directional type: two-way. Language Lab Headset Detail   Language Laboratory Headset Packing  1). Packing Measurement MODEL ITEM QTY(PCS) G.W.(KGS) N.W.(KGS) MEA(CM) GD709 RJ11 Headset 40 9.00  7.80  56*48*35 2). Packing Details   Payment & Delivery 1)Payment Terms: TT, L/C at sight. 2)Delivery Time: 10-15 days after getting the deposit Real Language Lab Headset Case