This is non corrosive, has capacity to absorb & retain moisture from the surrounding. Being non soluble in water, it stays at the place and in not washed out by the rain water/underground water. This mineral filling compound is highly conductive. Back fill compound : Back fill compound is a conductivity improver compound. It is a specially developed compound for having quality of highly conduciveness, non corrosive, absorbing & retaining the moisture for a long time.