SEDs of the γ-ray NLS1 galaxies in our sample, built using simultaneous Swift UVOT and XRT data in the observer’s frame. Simultaneous UVOT/XRT data are marked in the same colour. The UVOT data are corrected for Galactic extinction. The X-ray spectra are plotted using the best-fitting model parameters. The black points represent radio data collected from NED, including measurements by Bennett et al. (1986), Wright & Otrupcek (1990), Becker, White & Edwards (1991), Gregory & Condon (1991), White & Becker (1992), Laurent-Muehleisen et al. (1997), Condon et al. (1998), Healey et al. (2007), and Richards et al. (2011, 2014). The grey dotted line represents the SED model of PMN J0948+0022 taken from Foschini et al. (2012) and shifted vertically for comparison. In the case of 1H 0323+342, the large number of available UVOT spectra overlap strongly in this plot.