The Surefire Backup might be the best all around carry light ever made. Running on one battery and with two different settings for lumen, 5 lumens and 60 and with a good run time for both. My old Surefire E1E gets more use than any other light. I mean few people use lights to blind bad guys, normally you are going to use it for regular flashlight stuff. With this one you don't have to decide, since you can carry both in one package. You can read or navigate with the 5 lumen mode, yet still have the ability to use it as a defensive too at 60 lumens. All the while barely taking up more space than the single battery it runs on. Its not for everyone but if you are after a high end, high quality flashlight with a great warranty made by a great company this is the way to go.