Just a quick post. Tesco’s currently have these little headtorches discounted to £5. I have a lovely Petzl Duo Waterproof Headtorch which I have used since the mid 90’s. However, I tend to use one of these Energizer LED headtorches for my evening/night paddles and carry the Petzl in my emergency bag.
Its small, lightweight, has 3 white LED bulbs and one Red LED bulb which is great for not destroying your night vision. It runs off three AAA batteries. It’s not waterproof and the build quality is nowhere near as tough as a Petzl, however as a spare or for use where you would not want to damage/wear out your main headtorch £5 is a bargain.