8.3" X 11.75" LARGE 3X Fresnel Lens FULL PAGE Magnifier -- Solar Oven/Diy Projec
Here is the ultimate lens you need to have -- 1 full page 8.3" by 11.75" magnifier. They can work at various distances. Just don't put them right on the surface. These are durable and won't break or easily crack like glass does.