Merial- Dosage adjusts from 5 ml to 65 ml in 2.5 ml increments. Clear poly barrel is marked with proper pour-on cattle wormer dosage up to 1430 lbs. Adjustable tip of pour-on nozzle allows you to independently set the pressure at which pour-on wormer is dispensed. Comes with pour-on nozzle and 9' draw off tubing. Designed for use with Ivomec Pour-On or Ivomec Eprinex Pour-On cattle wormer.