REL Arrow Wireless Receiver for REL Subwoofer - Gen 2 - READ | eBay
Amazon.com: REL Acoustics Airship™ Wireless Subwoofer Transmitter Created for 212/SX, S/510 and S/812. Compatible with G1 Mark II. Not Compatible Serie T/i, Serie HT, Legacy Serie S or No.25. : Electronics
REL Airship II Wireless Transmitter - ListenUp
The REL 3D Subwoofer System and how it works - HomeTheaterHifi.com