A platelet apheresis product or single donor platelet (SDP) with a white blood cell content of 5 x 10(6) or below is considered optimal for transfusion. We modified the COBE spectra platelet collection protocol as follows: increased AC infusion rate of 1.1 ml/min/LTBV, setting the inlet: AC ratio configuration at high, and maintained the inlet flow rate of this setting with a maximum of 80 ml/min. The collection time varied with single dose or double dose production. The aim was to consistently obtain a platelet yield above 3 x 10(11) and a WBC content less than 5 x 10(6). The results were tabulated on 64 donations. The platelet yield was > 3 x 10(11) for 59 donations with a mean of 4.89, median of 4.72, and a range of 3.02 to 8.14; and < 3 x 10(11) for 5 donations with a mean of 2.74, median of 2.84, and a range of 2.14 to 2.96. The WBC content was < 5 x 10(6) for 60 donations with a mean of 0.52, median of 0.20, and a range of 0.06 to 0.71; and > 5 x 10(6) for 4 donations with a mean of 59.9, a median of 48.9, and a range of 8.12 to 62. We conclude that 93.8% of the donations yielded a SDP that met or exceeded leukoreduction standards.