The everbuild range of everflex 450 premium builders silicone sealants are 310ml sized cartridges that are available in 7 colours white brown clear black buff grey and oak all these colours will fit most common mastic or sealant guns everbuild 450 range of silicone sealants are cost effective low modulus oxime cure rtv silicone sealants that adhere to a wide range of both porous and non porous surfaces without the need for priming conforms to bs5889 silicone 450 is formulated as a high viscosi