250mm EFFICIENT Subwoofer 2" swing spool Multiple aeration system HPPC Membrane(High Pressed Paper Cone) PPTA Connex Spider Polkern drilling very stable housing reinforced dust cap LLE (Long Life Edge) Installation depth: 114 mm built-in Ø: 227 mm outside Ø: 261 mm Impedance: 4 Ohm 350/250 Watt Suitable for: 10 Inch