So far, this device has worked very well to alleviate my symptoms of SAD. I get pretty desperate between November and January when the darkness triggers negative feelings. I usually start a routine of vitamin D and sit in front of a sun lamp in the mornings but the routine wasn't helping much this year. I took a chance on this device after reading the reviews and doing the research. It works on the concept of transcranial brain illumination, i.e. shining light on your brain. It sounds goofy and I wondered how this could possibly work since we don't have light receptors in our ears. There were studies on the manufacture's website but they were done in another country and I was skeptical. Fortunately, I found a study on the National Institutes of Health (NIH) website saying that transcranial bright light treatment does work to relieve SAD related depression [...] The article says "Patients in all three groups showed significant decreases in their BDI, HAMA, and SIGH-SAD scores. Response rates, i.e., an at least 50% decrease of symptoms as measured by the BDI, were 74%-79% in the three treatment groups." The article also says "These results suggests that transcranial bright light treatment may have antidepressant and anxiolytic effect in SAD patients, as both self- and psychiatrist-rated depressive and anxiety symptoms decreased in all treatment groups." That was all I needed to try it. The headset arrived a day earlier than I expected. It feels like an iPod and it was charged and ready to use. I put it on for 12 minutes as suggested and went about doing my routine. I use it regularly, probably twice in the morning, once at work and twice in the evening when I return from work. I told you I get desperate this time of year! I swapped out the ear plugs because my ear canals are a little bigger but I used one of the larger ones in the box. The ear plugs are snug now. See the picture of the device when its in my ear and on. The device has one button that turns it on and off and can be used to reduce the timer from the default 12 minutes to less. There is one port on the device and it is a standard USB micro A slot that is used to charge the batter and to plug the headset. It is a smart looking little device. After two days, I had some noticeable improvements in my mood. I hope I can describe this well and that it makes sense to you but it feels as though a part of my personality turned back on. At work, I am smiling more, being more social and I am able to focus on my work. I see myself calm, laughing and seeking out company and conversation. I am not so consumed with how bad everything is. After work, I am wanting to socialize again and I have energy to go to the gym and run errands. I noticed my need to isolate myself and brood just kind of diminished and my happy self was showing up again. I could feel content with life again. I don't know if this will work for you but I am glad I tried it. I don't travel regularly so I don't know if it is good for jetlag but next time I do, I'll update this review. I still use my sun lamp in the morning and take vitamin d. I use the headset in addition to my winter routine. I know this device is expensive and I think maybe a less expensive model will get on the market eventually. For now though, I'm glad I found it. Again, I don't know how it works and I get it that it might be a placebo effect, but either way, it has helped.