1b is a Bluetooth speaker with two speakers paired It can be used by a single set or two sets in parallel. Note: one set of Q1b is one box. If you need to use it in pairs, please shoot two. Sabwoofer cabinet material:Wood; Woofer/Widerange material:Wood; Mid-range material:Wood; Sensivity:0dB; Bluetooth Version:4.2; Input Power(W):25-49 W; Total Harmonic Distortion:8%; Voice Control:No; Frequency Range:100Hz-20KHz; Output Power:5W; Display Screen:No; Waterproof:No; Support APP:No; Support Memory Card:No; Remote Control:No; Support Apt-x:No; Intelligent Personal Assistant:NONE; Display Screen:No; Built-in Microphone:No; Audio Crossover:Full-Range; Number of Loudspeaker Enclosure:1; Power Source:USB; PMPO:5W; Channels:3 (2.1); Battery:Yes; Communication:USB; Speaker Type:OUTDOOR SPEAKER; Cabinet Material:Wood;