Mason's hygrometer - spirit filled is a wall-mounted wet and dry thermometer for determining the relative humidity. The mason's hygrometer measures the wet and dry temperature over the range of -15 to 50°C. The Masons hygrometer is supplied with a slide rule for calculating the relative humidity over the range of 1 to 97% RH. It is manufactured from robust white ABS plastic and incorporates an integral hook for wall-mounting.
Dimensions are 34 x 75 x 310mm