brand new and high quality Features: Product adopts industrial-grade chip, high-precision SHT20 temperature and humidity sensors, ensure the products with good reliability, high precision and interchangeability. Adopt RS485 hardware interface (with the for lightning for protection design), the protocol layer for standard industrial Modbus Rtu protocol. This product integrating MODBUS protocol with ordinary, users can choose communication protocols, common agreement with automatic upload function(Connect the RS485 serial interface mode tool by automatically output temperature and humidity). Modbus Function Code: 0x03: Read keep register 0x04: Read input register 0x06: Write a single keep register Specification: Working voltage: for DC 5-30V Output signal: RS485 signal Temperature measurement range: -40 ~ +60 Humidity measurement range: 0%RH ~ 80%RH Temperature measurement accuracy: 0.5 Humidity measurement accuracy: 3%RH Dimensions: 2.9x4.6x6.5cm/1.14x1.81x2.56inch Color: White Quantity: 1 Pc Note: 1.Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package includes: 1 x Temperature & Humidity Transmitter