Comparison of the pulsating B-type stars with the theoretical instability strips for ℓ = 0 − 2 and three different metallicities Z_ini = 0.010, 0.014, 0.020. β Cep stars are marked by downward triangles, SPB stars by upward triangles, and hybrids pulsators by diamonds. The size of the symbol is proportional to the projected rotational velocity of the star which ranges between v sin i = 7 − 280 km s⁻¹. Hatched symbols mark variable stars where the exact contribution of g modes, rotational variability, and SLF is difficult to disentangle.