Preformed flexible laminate

A composite structure comprising;

• at least a first and second transparent or translucent panel members having facing, generally parallel surfaces spaced a generally finite distance apart from each other and a unitary seal located generally along the peripheries of said first and second members, in physical contact with the facing surfaces of said members, said unitary seal comprising
• a) at least one longitudinal core material
• b) at least one longitudinal adhesive film in physical contact with said core material and adhering said core material to said first and second members;
• and
• c) at least one longitudinal spacer element substantially perpendicular to the planes formed by said first and second members and having a width, measured perpendicular to said panel members, of less than or equal to said finite distance, said at least one spacing element being bendable perpendicular to its width to an angle from 2.degree. to 150.degree. without changing said width of said spacer element more than one tenth of one percent, said at least one spacing element extending substantially along the length of said unitary seal, and said at least one spacer element adhered to, partially embedded in, or embedded in said at least one longitudinal core material,
• said adhesive film of said unitary seal being compositionally different than the composition of said at least one core material and at least a portion of said longitudinal core material being located between said spacer element and a gas space defined by said first and second members and said unitary seal.