If You Care 100% Biomass Firelighters are 100% from renewable resources and are non-toxic. Because If You Care Firelighters are made 100% from biomass- wood and vegetable oil- the emission resulting from their combustion are considered carbon neutral. 28 pieces/lights 7-9 fires. To use place a few pieces under wood or on top of charcoal then light the fractured side of the cube.