A long-wavelength model for the turbulent magnetic fluctuations parallel to the magnetic field () has been implemented in the global gyrokinetic code GENE. The model provides a way to include this physical effect with little computational cost, permitting the study of on global nonlinear gyrokinetic simulations. The model has been verified through convergence tests and against an arbitrary wavelength solver, resulting in good performance up to moderately high wavelengths (). Using this approximation global nonlinear fully electromagnetic simulations were performed with Cyclone Base Case-like parameters to study the impact of on different plasma β regimes. A negligible impact for a low beta regime and roughly a doubling of the heat transport when including in a high beta KBM regime is found, which is in line with expectations based on linear studies and highlights the impact of in KBM driven scenarios.