Designed from the ground up for the GroBot, with a custom-wound motor, these peristaltics can handle concentrated nutrient solutions, full strength acids or alkalais. You get four (4) of these inside each GroBot EVO or Pump Rack. Good for keeping a spare around, or great for building your own custom systems to move nurtrients, fuel, oil or caustic chemicals. Surgical silicone tubing. Precision variable speed DC drive runs on 3 – 12 volts.