Boston Acoustics GTA-RSL - Car subwoofer level remote control - cable Remote Subwoofer Level Control Optional GTA-RSL remote subwoofer level for Boston GTA Amplifiers Can be flush or under-dash mounted Provided 16 cable connects at both ends to ease installation Compatible with GTA-502, GTA-802, GTA-504, GTA-1005, GTA-400M, GTA-800M models