This radiometer comprises a partly evacuated glass bulb about 70mm in Diameter mounted on a round base, containing at its centre a fine pivot which supports four light weight metal arms. One side of each vane is blackened , the reverse side is bright. When the light strikes the wings, it transfers the heat to each one, but not at the same degree.
Alcohol lamp perfect for any lab or home application. Polyhedral glass alcohol lamp -- allows for multiple angles. Metal cap. 120mL capacity.