I’ve figured out that I want to get a spare Surefire to keep in my car in case of emergency (my god, this addiction is emptying my wallet). I don’t need ultimate brightness, but would rather aim for runtime. I decided that I am just going to get some variety of the P60 setup due to its reliability and simplicity. For the illumination component, I want to get a KX4 head. Here is where I was getting confused. I found two models of the KX4, an 80 lumen model, and a 120 lumen model; each with 12 and 9 hours runtime respectively. Either of these models would be great for my needs. But then I’ve discovered the KX4-BKHA model. These seem to come with 120 lumens but only ~2 or ~3 hours runtime . Is this true? Should I really aim to buy a KX4 over a KX4-BKHA?