The energy efficiency class of this bulb is F. The brightness of a light bulb is measured in lumen, which in this case is 470 lumen.
Conrad Electronic
OSRAM 4058075808706 LED (monochrome) EEC F (A - G) E-27 Bulb shape 2.5 W = 22 W Warm white (Ø x L) 64 mm x 143 mm 1 pc(s)