PAC SNI-35 ADJUSTABLE 2-CHANNEL LINE OUT CONVERTER.USE WHEN ADDING AN AMP TO A FACTORY OR AFTERMARKET RADIO PROVIDES AN ADDITIONAL SET OF PRE-AMP OUTPUTS FROM A HEAD UNIT EQUIPPED WITH ONLY 1 SET LINEAR FROM 20 HZ?10 KHZ @ ?.5 DB, WHILE MAINTAINING SIGNAL PHASE ISOLATES INPUT & OUTPUT CIRCUITS TO PREVENT GROUND LOOP NOISE ADJUSTS THE SIGNAL FROM 2W?40W PER CHANNEL WITH SIGNALS BELOW 20 HZ CUT-OFF