BAL 31 Nuclease acts as an exonuclease, degrading double-stranded DNA and RNA from both 5"-phosphate and 3"-hydroxyl termini. This enzyme also possesses single-stranded DNA and RNA endonuclease activity and is capable ofcleaving at DNA/RNA nicks and gaps. It requires Ca²⁺ as an essential cofactor for its exonuclease and endonuclease activities.

BAL 31 Nuclease is supplied in 20 mM Tris-HCl (pH 8.0), 100 mM NaCl, 5 mM CaCl₂, 5 mM MgCl₂, 1 mM EDTA and 50% glycerol.