This is a JBL BP600/1 Subwoofer Amplifier. FOR SALE AT ONLY $550!!!! This amplifier retails at $400. It has been custom modified by Custom Sound of New Jersey with a JL Audio R.I.P.S System, which retails for $379 plus an installation fee of approximately $150. The R.I.P.S System is a truly unique feature, enabling the amplifier to create extremely powerful sound usually created using massive power, this amplifier provides the same massive sound created by massive power with any amount of power availble, be it a large amount of power or a tiny amount of power. . To learn more about the JL Audio R.I.P.S System please visit the following link: http://www.jlaudio.com/amps/rips.html. Maximum output at 4 ohms is 300W x1. The maximum output at 2 ohms is 600W x1, this is before the R.I.P.S system was installed. It currently produces in excess of 1000RMS at 4 ohms (with the R.I.P.S System installed) I used this amp in my vehicle for a month, using it to power one JL Audio 13w7. Previous to this amplifier, I was running a JL Audio 1000/1 to the 13w7, and this amplifier (the one advertised in this auction) far exceeded the performance of the JL 1000/1. Complete specs on this amplifier (before the R.I.P.S System was installed) is available on the manufacturers website at the following web address http://www.jbl.com/car/products/product_detail.aspx?prod=BP600.1&ser=POS&cat=AMP. The JLB owners manual of this product is available at this web address: http://manuals.harman.com/JBL/CAR/Owner%27s%20Manual/bp_om.pdf. This is a truly amazing amplifier, produces an amazing quality of bass with that great "hitting" sound you've been dreaming of. The amplifier is practically brand new, used minimally for only a month, is in great shape, has certification stickers on back of amp from when purchased, as well as proof of R.I.P.S System installation. I have many pictures of this item available, so please email me at alex.adamo@verizon.net if you request pictures or more information. Since this item is very heavy shipping charges are estimated at $20 (insured UPS shipping, the amplifier will be wrapped in bubble wrap and the box will be lined with bubble wrap and filled with styrofoam before shipped) I am able to arrange for alternate methods of shipping if you are not able to accept UPS, email me for details. This item is also available on eBay with some pictures available at this web address: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3089120968. Please email me if your interested in buying this item. Thanks