Possesses two activities: a DNA synthesis (polymerase) and an exonucleolytic activity that degrades single-stranded DNA in the 3' to 5' direction. Has a template-primer preference which is characteristic of a replicative DNA polymerase. a 2'-deoxyribonucleoside 5'-triphosphate + DNA(n) = diphosphate + DNA(n+1) Exonucleolytic cleavage in the 3'- to 5'-direction to yield nucleoside 5'-phosphates. Heterodimer of a large subunit and a small subunit. Belongs to the DNA polymerase delta/II small subunit family.