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Five tiny black rectangular digital hygrometer thermometers with LCD screens

Rojuna Mini Thermometer Hygrometer Black Ro-2022027 (5)

SKU CH-XJW9-2GPSZ

Pack of five compact black digital gauges track indoor temperature from -58 to 158 and humidity from 10 to 99 %RH with ±2 accuracy

  • TypeThermometers
  • ColorBlack
  • FeaturesHygrometer, ±2
  • Measurement Range70 degrees_celsius
  • Measurement Accuracy±2
  • Operating Environment70 degrees_celsius
  • Monitors temperature and humidity every 10 seconds
  • Accurate within ±2 °C and ±5 % RH
  • Compact 2.87 × 2.51 × 0.51 cm fits tight spaces
  • Covers -58 °C to 158 °C and 10 % to 99 % RH
  • Five black units ready for jars, fridges or greenhouses

Compact monitor for small spaces

The Rojuna Mini Thermometer Hygrometer in black fits inside mason jars, guitar cases, greenhouses and fridge corners. Each unit measures 2.87 cm by 2.51 cm by 0.51 cm and uses a built-in probe to sample conditions every ten seconds. The five-pack lets owners scatter sensors across a cellar, attic or garden without extra wiring.

Passive operation with no fan noise

The device draws minimal power from its internal cell and runs silently because it has no moving parts. Operating and storage environments are both rated to 70 degrees_celsius, so the unit tolerates warm greenhouses or cold fridges without active cooling. Temperature accuracy is ±2 and humidity accuracy is ±5%RH across the stated ranges.

Five identical gauges for distributed readings

The bundle supplies five separate meters so users can track micro-climates in different jars or rooms simultaneously. No companion app, wireless link or calibration software is included; each gauge simply shows the current temperature and humidity on its own LCD. Buyers who need data logging, alerts or a single consolidated dashboard will need a different solution.

Highlights

  • Monitors temperature and humidity every 10 seconds
  • Accurate within ±2 °C and ±5 % RH
  • Compact 2.87 × 2.51 × 0.51 cm fits tight spaces
  • Covers -58 °C to 158 °C and 10 % to 99 % RH
  • Five black units ready for jars, fridges or greenhouses

Specifications

BrandRojuna
TypeThermometers
ColorBlack
Part NumberRo-2022027
FeaturesHygrometer, ±2
Measurement Range70 degrees_celsius
Measurement Accuracy±2
Operating Environment70 degrees_celsius
Storage Environment70 degrees_celsius
Dimensions2.87 cm x 2.51 cm x 0.51 cm

Questions about this item

How do I install the Rojuna Ro-2022027 thermometer hygrometer in a mason jar and what step is often missed?

Place the 2.87 cm x 2.51 cm x 0.51 cm unit inside the jar and seal the lid; the step often missed is ensuring the LCD remains visible through the glass for readings.

What maintenance will the Rojuna Ro-2022027 need over time?

Replace the internal button cell when the LCD fades; no calibration is required as temperature accuracy stays ±2 and humidity accuracy ±5%RH.

What is the first limit reached if the Rojuna Ro-2022027 runs continuously in a hot environment?

The operating environment limit of 70 degrees_celsius is reached first; beyond this the device may stop measuring every 10 seconds.

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