Eltako Wireless hand-held transmitter FHS2-al/anso without battery or wire, with rocker, aluminium/anthracite-soft

Wireless 2-way hand-held transmitter FHS2-al/anso with rocker aluminium/anthracite-soft, 49 x 47 mm, 16 mm high. Weighs only 37 grams. Generates the power for wireless telegrams itself when the button is pressed, therefore there is no battery. Smart Home sensor.