Looks like it's mainly a mix of 4a and 4b. I'm not sure if some ends are 3c ends or if they're just the heat damaged ends.
型YPE 4A/4B 疎OARSE 低OW POROSITY 尚IGH DENSITY
TRANSITIONED: Since Dec 23, 2010 (我 想hink...)
BC DATE: July 23, 2013 (about 31 months)
7/23/13 :: SL
1/9/14 :: CBL