They are the same mailers as used by Amazon for mailing out their books, and the original Bukwrap brand. All our book wraps contain 'peel & seal' strips with permanent strong adhesive for easy and efficient application and use. A pallet of 1950 x large C4 / A4 size book wraps, also known as cardboard mailers. The size of these quality wraps is 326x245mm (length x width), and the depth is adjustable between 0-70mm. Perfect for A4 size books, as well as slightly oversized A4 cook books, these are extremely high quality cardboard mailers manufactured in the UK.  The C4 size of mailer represents a packet size for royal mail purposes. The weight of each mailer is 125g.