Silaform silicone putty is a one-to-one mix material that is excellent for a variety of procedures. Silaform 90 (blue) has a Shore A hardness of 90 while Silaform 70 (purple) is more flexible and has a Shore A hardness of 70. Both materials resist deformation and abrasion normally associated with silicone putty. The absence of expansion and contraction offers endless possibilities for this economically priced product. Indicated for use with duplicating materials.