This is our latest incarnation of a performance proven class A MOSFET amplifier, with reference to F5 class A amplifier. In this incarnation, we have make the boards bigger, tracks wider on the output and power section, and features the output device using TO-3 package MOSFET. TO-3 MOSFETs are ruggedized, hermetically sealed and has much better thermal property than the TO-3P plastic package counterparts. PCB dimension : 138mm x 76mm PCB thickness : 1.6mm Copper thickness : 70um ( four times normal thickness !) Surface : Gold plated This is a single channel amplifier PCB. Two PCBs are needed to form a stereo amplifier. We provide schematic and part list to buyers by EMAIL( to be attached to the shipment notice). The assembled board is to illustrate how the board and the power MOSFETs are to be mounted onto the heatsink. This listing is for bare board only, no component or heatsink included. We also have the power filtering board with reference to First Watt amplifier series that is a perfect match with this amplifier board. Please check our other auctions. We do air shipping worldwide at US$4.50. We welcome combine shipping. Powered by SoldEazy