Rupture forces of B:b and A:a knob-hole interactions detected as voltage signals calibrated in force units. Portions of digitized raw data obtained using different surface-bound molecular pairs showing the forces exerted by the trap on the latex bead during a series of contacts (upward deflections) and separations (downward deflections). (A) Extended sequence of the B:b interactions appearing as weaker and variable rupture force signals. (B) Extraction from the data in panel A, showing a stepwise unbinding event indicative of multiple knob-hole interactions. (C) Extended data trace and (D) extraction of the A:a interactions appearing as strong homogeneous signals determined using laser tweezers and described in detail elsewhere.¹⁰