The Aquameter is a leave-in soil moisture sensor pen that can be left in the soil for continuous monitoring, unlike other moisture meters that need to be taken out after each measure. Dimensions: (small) - Intended for pot sizes of 6-15cm - Ideal for small succulents Set includes five refillable watering sticks (green) - Moisture meter for house plants that has refillable replacement core - Each stick last for approximately 6-. This soil aqua meter has plant water indicator that changes color depending on soil type - White indicates watering; blue indicates it's been watered., Manufacturer: CTRLZS