I purchased a bass last night and on the headstock it says Fender Precision Bass Active. It has a CNxxxxx serial number. I was wondering if anyone can help me out with this as to what it is and where its from, also it has an active/passive switch with a red LED that indictates on or off and in the back the battery covers has an opening in which one can insert a screwdriver to adjust the intensity of the preamp. Is that stock for those CN guitars or is that an after market thing. Oh and it also came with a Wilkinson fully adjustable bridge. I bouhg it because it played like butter and the combination PJ pickups sound really good and I only paid $140 US for it. Please help.