The branching fraction for the semi-inclusive process B→ήXs, where Xs is a strange hadronic system, was measured. The Xs mass spectrum was also obtained, which fits into models predicting high masses. Two tracking devices, a silicon vertex tracker consisting of five layers of double-sided silicon microstrip detectors and a 40-layer central drift chamber, were used for the detection of charged particles. It was found that the charged-particle identification was provided by the average energy loss in the tracking devices.