Sperm-Chex Post VC is a positive/negative control that validates the laboratory’s manual post-vasectomy sperm counting procedure. Sperm-Chex Post VC is the only manual post-vasectomy sperm count control that contains stabilized sperm cells. Competitor quality controls contain latex beads which do not have the same chamber loading or optical characteristics. Sperm-Chex Post VC can be used like a patient sample and provides a positive sperm count and negative sperm count sample.