The Snap On ¼” 12mm swivel shallow socket is the perfect tool to remove the 12mm flange nuts on the EGR. I needed to remove to access the dummy end cap valve cover which was leaking oil; o-ring was deformed after 15 years. I used the Snap On shallow socket plus a 10" extension, ratchet, and iron pipe to break free the two nuts. A normal socket will not seat correctly on bottom nut because of the very tight space and will round off edges. The Honda OE 12mm flange nut part is 94050-08080 and Honda OE gasket part no 18715PB2000 (Ishino). I would not hesitate to purchase any Snap On product.