The main difference between the two fixtures is that the Top Dog (TD) is more versatile overall. The glare guard and lens cover are a unit on the Fat Boy (FB). On the TD, the glare guard can be adjusted more finely or even be removed entirely. The FB has indexed adjustments at the knuckle. On the TD, finer angle adjustments are possible. There may also be differences between wire length options and lamp beam spread options. Hth.
