A clip of the present application generally comprises a first clip member, a second clip member, and a retention feature. The first clip member and the second clip member are coupled together and capable of being placed in at least two positions. In the first position, the clip is capable of receiving a bag containing a fluid, and, in the second position, the bag is capable of being held between the first and second clip members. While the clip is holding the bag, two or more pockets are formed in the bag, and the fluid is generally restricted or prohibited from transferring from one pocket to another pocket while the clip is in this position. A retention feature retains the clip, which is holding a bag, to a centrifuge receptacle and allows the clip to be placed in a predetermined position on the centrifuge receptacle.
