keV to GeV diffuse extragalactic background. The red line shows our estimate of the contribution due to the IC/CMB arising from extended lobes of FR II radio galaxies. The gray area represents the uncertainty in the estimate of the contribution to the EGB and arises mainly from the uncertainties related to the SED template and the estimate of the K constant. The legend shows the symbols corresponding to the data of Fukada et al. (1975), Watanabe et al. (1997), Weidenspointner et al. (2000), Ajello et al. (2008), and Abdo et al. (2010b).