well i just bought some 12" p1 and a p2002 and the guy a bought it from gave me this as well... http://www.rockfordfosgate.com/products/product_details.asp?cat_id=5&series_id=42&family_id=102&item_id=55412&locale=en_US&p_status= .and am not sure what exectly its for as i have a aftermarket cd player so i shouldnt need it right i should just need to use the RCA cables