This is a clay-like substance which resists blasting when using shadow in a "single process". It is also ideal for masking shadow in a single process - shape carving. It is applied after the stencil is removed, being easily pressed into letters or carving background with finger or putty knife. It is washed out the letters with water. Blast Mask comes in a plastic bag and is kept soft and pliable.
Available in 25 Lb. blocks.