Like the Large Esbit Fuel Cubes, this smaller version, just 4 grams each, is a perfect fire starter or source of quick heat. Esbit Fuel Tabs are safe and cannot self ignite. We recommend the Esbit 4 Gram Fuel Cube for smaller survival kits or anywhere a fire starter is needed. The 4 Gram Esbit Fuel Tablet will light with a match, or just about any source of flame and burn long and hot enough to get a roaring fire going if used properly. We include the Esbit 4 Gram Fuel Cubes in many of our high quality survival kits. There are (20) Esbit 4 Gram Fuel Cubes to a box. Each burns for approximately 5 minutes.