Product description Material: plastic + metal Color: Black Size: 16 * 6 Probe length: 8cm Package Contents: 1 * Soil pH Tester 1.2-in-1 function Test soil pH value of plant ,quickly helps you specialize in grasping when you need to water your plant, control the pH value in the soil. 2.Accurate and reliable Premium Double-needle Detection Technology strongly enhances the speed and accuracy of detecting and analyzing soil pH acidity, refuse to be a killer of plants, promote plant growth in a healthy way. 3.Easy to use Just insert the sensor probe into the soil about 15cm, toggle switch to test pH value, fertlity you would like to measure, then wait for a few minutes till the pointer stops swinging to get a stable reading on the scale dial. If the plant is very dry, the soil pointer will not swing, that means your plant needs water. 4.COMPACT FOR INDOOR & OUTDOOR USE: Portable and easy to carry to anywhere you want .Know when to water, adjust pH, or change lighting for your flowers, plants .Refuse to be a killer of plants, promote your plant growing in home , garden, lawn or farm etc. 5.No Battery Needed No batteries or electricity needed, ready to use out of box. Plug and read.