Heavy duty board back envelopes are ideal for books, certificates, magazines and legal correspondence. The hard back envelopes come distinctly with 'please do not bend' printed on the front for your mails to arrive safely and in perfect condition. Board backed envelopes provide maximum protection for bendable items like photographs, certificates and prints. Available in sizes like A3 envelope, A4 envelope and A5 envelope, the hard back envelopes come with peel and seal closures for easy sealing and extra security. Items placed inside the envelopes are not visible through the material and they are mainly used by online businesses, mail houses and professional firms. Purchase with us at wholesale prices and get free shipping above £20 for every purchase.