This buffer contains 5 mM Tris-HCl pH 8.0 and 0.2 mM CaCl2. Used as a general G-actin (monomer) buffer with the addition of 0.2 mM ATP (see Cat. # BSA04) and 0.5 mM DTT (A-buffer). The buffer can be changed to a general F-actin (filament supporting) buffer by the addition of 1/10th volume of actin polymerization buffer (see Cat. # BSA02)