A one-part, neutral-curing, ultra low-modulus silicone sealant that will not stain natural stone such as marble and granite and that reacts with atmospheric moisture to form a durable, flexible building sealant. Pecora 890NST performs exceptionally well under dynamic conditions due to its ultra-low modulus, high extension/ compression, recovery properties and strong adhesion to most building materials and accommodates long-term movement of +100-50% in properly designed joints.