Dear we are using rtv silicon rubber with tin catalyzer as temporary filler in a wet mould of alginate. Because it is temporary(low quality) we need a very economic priced (max 2,5$) white rtv silicon. The specific weight/gravity with max of 1,3 hardness Shore A 15-30 . Shelf life 1 1/2 year Do you have some suggestions ? We can order tons Best regards, Paul Pieck Co- founder Wonderboys Show More