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White C3 Cardboard Envelopes are the perfect choice for sending A3 sized important documents which need to be kept flat during transit. Our range of white C3 cardboard envelopes includes our all board envelopes – a premium quality, smooth white robust cardboard envelope, as well as classic board backed envelopes which combine a rigid board backing and a strong paper front to keep your items flat. Both of these envelopes include a peel and seal adhesive strip closure for fast packing which gives a reliable seal, and fit within Royal Mail medium parcel sizing. All of these envelopes are fully recyclable, biodegradable, and completely plastic free. Supplied in boxes for easy handling and neat storage.
Please note: C3 size is up to 324 x 458mm, designed to fit A3 sized items of 297 x 420mm.