This fresnel lens is the largest one that we stock. On a sunny day, you can easily light any tinder in a matter of seconds. They are so powerful that we take them outside and make the concrete smoke every now and then.
A fresnel lens is a fast and efficient way to start fires on a sunny day. Fresnel lenses act like magnifying glasses, which means that you can focus the sun's rays on a small point to instantly light many kinds of tinder. Char cloth works especially well in combination with a fresnel lens.