Abstract: A sterile cover tube for ultrasound probe and electrical cable has a telescoping tube having a closed end and open end. The telescoping tube is extendable to cover the ultrasound probe and electrical cable. A sealed pouch containing coupling agent is disposed adjacent to the closed end of the telescoping tube. The sealed pouch has a breakable seam or membrane. The sealed pouch can be placed over the probe head prior to placing the cover tube over the probe and electrical cable. The sealed pouch is ruptured by pressure to release the coupling agent over the ultrasound probe after the telescoping tube has been extended over the ultrasound probe and electrical cable. The coupling agent covers the probe head with a thickness of 0.2-6.0 millimeters after the sealed pouch is ruptured to provide an airless medium for an accurate image of the body region of interest.