Abstract: An apparatus for transporting blood samples within a capillary tube using a rigid plate member to protect the capillary tube during transport. A magnet is magnetically coupled with and thereby moves a ferrous metal flea within the capillary tube to promote mixing of the blood sample and an anticoagulant chemical coating on the inside of the capillary tube. The magnet is slid along the length of a recessed guide track or guide members to assure that the magnet does not come in contact with the capillary tube with sufficient force to break the capillary tube. The magnet has a central archway through which the capillary tube extends to increase the magnetic coupling between the magnet and the flea and yet prevent contact with the capillary tube. The capillary tube is held within an alignment groove in the rigid plate member. In one embodiment, a holder holds the capillary tube against the rigid plate.