Everbuild builders silicone sealant 450 everbuild 450we 450 builders silicone is a premium quality low modulus non corrosive neutral cure silicone sealant that adheres to virtually all substrates both porous and non porous typically used for construction expansion joints and perimeter pointing of all types of door and window frames conforms to iso 11600 class f 25lm everbuild 450we builders silicone sealant white 310ml 450