CICO Seal T 680 Polysulphide is two pack Polysulphide based joint sealant available in GUN GRADE and POUR GRADE. CICO Seal T 680 Polysulphide gun grade is a gun-applied, non-sag type for vertical joints and CICO Seal T 680 Polysulphide pour grade is for horizontal movement joints. When two packs are mixed, i.e. Polysulphide resin (Pack-A) with curing agent (Pack-B), it forms a tough, flexible, durable rubber like material with strong adhesive properties on most building substrates and joints.