SED of MKN 501 (1WHSP J165352.2+394536) at z = 0.033, a TeV detected HSP showing strong variability in X-rays (Swift-XRT, indigo dots). The giant elliptical galaxy template is represented as green solid line, at z = 0.033. The cross-circle marker represents the four IR WISE channels, and the contamination from W1 (3.4 μm) and W2 (4.6 μm) is clearly seen. The solid lines represent the average non-thermal emission.