This is a Main Board for a Sony VCR SLV-N51 unit that was tested before it was removed from the donor unit. It's important to note that this item is being sold as parts only, and therefore we are not able to comment on the condition of the board itself. This is a great opportunity to grab a spare part for your unit or to use it for repair purposes. This Main Board is compatible with units that have 4 heads, and it was manufactured in China. If you have any questions about this item, please feel free to ask.