IR iirc
If I remember correctly, a couple of infra-red LEDs worn at about forehead level are enough to blow out the vision of most CCTV cameras. Being IR, it's not so obvious as walking around with a bright torch strapped to your head, well until the CCTV watchers vector the police to you cos I'm not sure of the legality.
Amazon do a 3w IR Torch for about a tenner. https://amzn.to/2H0w9Tw
Biting the hand that feeds IT
