Extinction-corrected NIR PLRs for Type II Cepheids in the Galactic bulge. The violet and red symbols represent BLH and WVR stars, respectively. The dashed line represents a single regression line fit over coloured symbols and small symbols represent the Type II Cepheids displaying evidence of approaching saturation in the long period range and 2σ outliers in the short-period range. H-band data for WVR stars are also close to saturation limit and therefore we do not include them in linear regression fit.