I suppose the three dots represents a Grade 5 fastener, I'm not familiar w/ "08" or "80" (8.8, etc. is metric, Gr.8 is six marks). Anybody?
Anyway, often, a 12-point hex will be a reduced size from what would ordinarily be used to drive them.
The newer SBC head bolts for instance, are flanged 1/2" hex- flanged to better distribute the pressure. They were a 5/8" hex head, non flanged. This was fine for the most part, but did require the OEM rocker arms to be loosened before those head bolts could be turned. Of course, the aftermarket has had smaller heads available- for a price.
IIRC, some U-joints used them, too.