Thermals unlike regular NV can be used 24 hours a day. It's perfectly legal to hunt with either but only during 1/2 hour before sunrise and 1/2 hour after sunset. But we know the thermal is actually useful in daylight and won't be damaged and you can see critters through the brush. I have a NV monocular. It's basically a fun party toy my friends get a kick out of looking at stars. But if I decide to walk into a field at night, unarmed, and observe wildlife without harassing them, I'm within the law. Rules for thermal optics are the same.