SUSTEE can be used for almost all plants that grow in soils with a certain level of moisture retention: from bog moss to gardening culture soil, Akadama soil, black earth, bark, coco peat, peat moss, and vermiculite.
SUSTEE should sense moisture around the plant's roots at the bottom of a pot. So it needs to be placed close to the plant itself, within a 20 cm radius.
Incorrect watering is reported to be the cause of
80% of the time, the plant wilts.
They wilter because they are not thoroughly watered.
However, too much water leads to root rot more often than you would think. 
Japanese farmers say that "it takes three years to learn to water plants properly."
This goes to show that even professionals struggle.

The first moisture checker with pF indicator for your home.
For the first time ever, a home-grade moisture checker has been equipped
with a pF indicator (available water capacity).
This way the root's ability to absorb water - or
the plant's "thirst" becomes visible (patented in Japan, No. 5692826).
The high quality of SUSTEE prevents root rot caused by improper watering.
To better our product we keep testing and researching in cooperation with
the Tokyo University of Agriculture and farmers.

Sizes:
S pot size 2, 2.5, 3
Diameter 6〜9cm
Pots that can be lifted with one hand.
W10mm×D8mm×H120mm / 4.3g

M pot size 3.5, 4, 5, 6
Diameter 10.5〜18cm
Pots that can be lifted with two hands.
W10mm×D8mm×H180mm / 5.9g

L pot size 6〜12
Diameter 18〜36cm
Large pots that can only be lifted with excessive force.
W10mm×D8mm×H255mm / 8.0g