- Arm 2 will entail holding whole blood units at 1-6°C after collection for ≥ 66 hours (both IP and CP) prior to initiating cold filtration. Following refrigerated centrifugation and subsequent separation, SOLX® PRBCs will be placed at 1-6°C within 72 hours of collection (both IP and CP). Plasma will not be evaluated for this arm and will be discarded. The first donation will occur with product indicated per randomization and the second donation will occur with product alternate to the randomization.