These ashlar blocks likely acted as a plug for the possible threshold 7353 they cover between room H-9 and room H-11. It is thought that 7353 is a previous threshold for room H-9, perhaps giving access to the Via Praenestina, which was later renovated and possibly plugged by these ashlar blocks 7354 and 7355. This plug was likely completed by the addition of 7355 to the south. By this, 7354 then possibly completed the North-South running party wall between room H-9 and H-11.