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Black Letter Cardboard Envelopes are the perfect choice for keeping your smaller items flat during transit whilst ensuring your mail delivers an excellent first impression. All of our black letter cardboard envelopes are Board Backed Envelopes; combining a rigid black backing board to ensure items don’t bend in transit, and a strong black paper front to make your envelopes lightweight, and sized to comply with Royal Mail sizing to keep your postal charges to a minimum. Available in C6 and C5 sizes, these black letter cardboard envelopes are the perfect choice for securely sending A6 and A5 sized important documents in a recyclable, biodegradable, and plastic free mailer.
Please note: Letter sizing is up to 240 x 165 x 5mm with a 100g weight limit.
