If you run two pairs of these speakers (4 speakers), the impedance will drop to 4 Ohms. Please make sure that your amplifier is 4 Ohm compatible before setting up 4 speakers. Housed in a rugged ABS plastic casing with a subtle, yet durable mesh grille, these speakers will look stylish & discrete in most environments. Each enclosure contains a high quality 1 Inch balanced polymer tweeter (double the size of most on the market) and a 3 Inch surround woofer to produce a great sound for such a compact speaker. There is an adjustable mounting bracket on the back of each speaker allowing you to securely position each speaker where it needs to be.2-Way Speakers Speaker Cable Connections Max Power 8Ohm - 60w Power RMS 8Ohm - 30w Sensitivity (1m, 1W) - 88DB Frequency Response - 120Hz-20kHz Impedance - 8 ohms. Height 150mm, Width 105mm, Depth 105mm (Per Speaker). We also stock a great range of stereo amplifiers and speaker cable allowing you to create a brilliant and low cost surround sound or PA system easily.