Etekcity 2 Pack Indoor/Outdoor Soil Moisture Sensor Meter, Plant Care Hygrometer (Certified Refurbished) This Certified Refurbished product is tested & certified by Etekcity to look and work like-new. The product includes all original accessories, and is backed by a 90-day warranty Measure soil's moisture content by just plugging in the probe No batteries or electricity needed, plug and read moisture meter Color coded reading system, from red, green to blue Easy to read moisture levels, including ten scales, Compact and portable design for indoor/outdoor use