Features: Aluminum alloy shell (golden), acrylic lens, small size, thin body and light weight. Easy to carry, can also be hung on the wall. No battery needed, mechanical movement. Function: this hygrometer is a good way to track indoor moisture content. Application: humidity measurement widely used in office, workshop, school, warehouse, etc. Easy to install: designed with suspension holes for easy hanging on the wall surface. Specification: Product Name: 57mm diameter golden aluminum shell hygrometer Material: Aluminum Shell Color: Golden Diameter: app. 57mm/2.24in Thickness: app. 12.5mm/0.49in Measurement: relative humidity 0-100%RH, accuracy +/-5%RH (40-70%RH) Quantity: 1 pc Note: Transition: 1cm=10mm=0.39inch No retail package. Please allow 1-3cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Package includes: 1 x Indoor Hygrometer(other accessories demo in the picture is not included.)