The vas deferens, also known as the ductus deferens or sperm duct, is a long muscular tube that is part of the male reproductive system. It is a continuation of the epididymis and transports mature sperm from the testicles to the urethra before ejaculation. The vas deferens is surrounded by the spermatic cord and is partially coiled, with some parts being straight. It can be 30 to 45 centimeters long and is made of fibrous and muscle tissue. The vas deferens exits the abdominal cavity through the inguinal canal and connects to the ejaculatory duct. The vas deferens has a dense sympathetic innervation and produces strong peristaltic contractions during ejaculation to aid in the propulsion of spermatozoa.