To protect samples, reaction batches, or cell cultures from both contamination and evaporation, compatible lids are available for all BRAND plates and microplates. The lids are made of crystal-clear polystyrene and are optimally matched to the corresponding microplate, so that plates with lids can be stacked. The cut-corner sets the orientation of the lid. Lids are available with and without condensation rings for 96-well standard plates. In case the multiwell plate needs not only to be covered, but also securely sealed, self-adhesive films are available. These film sheets can be applied on the plates and removed without the use of expensive equipment, or can be applied with a hard rubber roller to ensure secure and uniform attachment of the film to the plate. The sealing films are available in different materials especially suited for storage, immunoassay, or cell and tissue culture.