These are a pair of Precision Power PC10 subs, Mounted in a Ported box. This box was specifically made for these subs and has custom ports. The box is made our of 3/4 mdf wood. The subs sound great. Has a flat piston cone design. These subs are 8ohms and hold 250 rms, 500 max. The box is wired for a 4 ohm load so all you need is 1 channel on a amp. These subs allow for a flexible system design. They work great and sound great. 100 plus shipping.