A clear holder keeps both sides of the card visible and is useful when credentials contain information on the front and back. A coloured holder can support department identification, visitor classification, temporary access levels, or event organisation. Opaque sections may conceal information on one side or provide a stronger visual border around the credential. Colour should not interfere with barcodes, photographs, magnetic stripes, or printed details that must remain readable. Consider lighting conditions and whether the badge will be scanned through the holder. A sample should be tested with the actual card design, attachment, and access system before a colour is adopted across an entire organisation.