High strength, permanently flexible acoustic sealant and adhesive When used as an adhesive the formula bonds plasterboard to plasterboard and other common substrates including blockwork, wood and metal studding When used as a sealant this formula remains permanently flexible whilst being resistant to mould, non flammable and over paintable Using Everbuild Everflex AC50 as both a sealant and a adhesives in a area creates an acoustic barrier to S EN ISO 140/3 standard when applied correctly Apply using a caulk, sealant / adhesive cartridge application gun, we recommend the Everbuild Power Pro Heavy Duty Sealant / Adhesive Cartridge Applicator Gun, Weight: 1.409999811525689 Pounds, Manufacturer: Sika Everbuild