At the heart of the new Powerblock² is the 700ASC2 ICEpower module. The 700ASC2 is the latest ICEpower module and integrates essential features, such as a comprehensive protection scheme against over-current or over temperature. The Powerblock² utilizes two 700ASC2 modules with a heavy 1/4-inch aluminum heatsink plate strapped across the units700ASC2 Harness: 1200AS1-2 Harness: ICEpower ASX Series: 50ASX2 Harness: 125/250 ASX2 Harness: 125/250 ASX2 Pro Harness: 700ASX Harness: ICEpower ASP/A Series: 250ASP Harness: 250A Harness: 250A(x2) Harness: 500ASP Harness: 500A Harness: 500A(x2) Harness: 1000ASP Harness: 1000A Harness: ICEpower Others: ICExtend Harness:Now available is an ICEpower® Amplifier Upgrade for your older BASH® powered subwoofer. Qualifying models are: XS15, XS15se, XV15, XV15se, XS30, XS30se, XV30, XV30f, and XV30Fse. The total cost for the upgrade is $374.99, which includes free shipping to the lower 48 States.