Alpine RS-W10D2 Sub 10" 25cm R Series Shallow Subwoofer Dual 2 Ohm 600w RMSUltra Shallow Design and Powerful Bass Output RS W10D2 10 (25cm) R Series Shallow Subwoofer with Dual 2 Ohm Voice Coils The New R Series Shallow Subwoofers With an ultra shallow subwoofer design and powerful sound output, the R Series Shallow Subwoofers give you the best of both worlds in size and sound. More bass with less space Alpines new Shallow R Series rise to the top, giving you extraordinary bass performance in an ultra compact form to suit