This SU is a row of ashlar blocks lining the southern limit of room G-20 east of the channel SU 6096. There is significant amounts of soil deposited between each of the stones, indicating that they have been moved and were not part of a wall structure in their current position. There appears to be three blocks: the two eastern most blocks are whole, while the eastern block is broken in at least three places. The eastern block is split into two pieces and then additionally is cut by the channel SU 6096. The basalt road curb SU 7020 does not continue between SU 6280 and the road 7019, and thus SU 7020 appears to have been robbed out of this area. While the original function of SU 6280 is unclear, one hypothesis is that they may have served as some new boundary area between the road SU 6280 and room G-20. There is a significant gap filled with soil between the two most eastern blocks, suggesting there might have once been an opening or possibly now-robbed-out threshold between the blocks.