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  • Envelope-like mailers manufactured from 100% recycled and recyclable material
  • Three types of capacity mailer available:
    M spec expandable - heavy duty with largest expansion
    Standard solid board - light to medium duty
    Premium corrugated with micro-flute - medium to heavy duty
  • Equipped with peel-&-seal closure strip and easy open tear strip
  • Scored for increased capacity:
    Up to 40mm for standard and premium
    Up to 70mm for M spec

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Capacity book mailers

We stock two different strengths of capacity book mailer: standard solid board and premium corrugated featuring a micro-flute. All of our mailers are gusseted to allow them to act as a small postal box when goods are inserted. Each size also complies with Royal Mail PiP guidelines so you can send your items with a clear idea of postage costs. Other features include a tear strip for easy opening and peel strip for secure closure. See more infos in the table for specification and detailed diagram.

M spec mailers

M spec mailers, or cardboard capacity envelopes, are expandable corrugated mailers which pop out into boxes, providing a versatile carrier for goods of all kinds. They are particularly useful for ecommerce businesses with large product profiles.

What are the benefits of using M spec mailers?

These gusseted envelopes can carry items when flat in mailer form or when they have been made into a box, providing a versatile and adaptable packaging method for businesses.

A layer of E flute corrugation sufficiently protects goods during shipping, providing excellent crush resistance and compression strength, ensuring packages do not bend or crumple when they come into contact with other boxes or heavy items. An adhesive peel-&-seal strip makes for quick, secure seals, while pre-creased grooves allow users to easily pop the envelopes out into a box, improving pick and pack efficiency for greater order fulfilment and cost savings. For effortless, mess-free opening, an easy tear strip is also included, promoting user satisfaction.

These mailers are far more cost-effective when compared to boxes thanks to their compact design. They take up less space on delivery vehicles, meaning more packages can be transported per journey and leading to a reduction in the carbon cost of shipping. Requiring minimal storage space, these are perfect for ecommerce businesses that have limited space.

M spec mailers are perfect for big pick and pack operations, distribution and ecommerce, especially businesses shipping out lots of small goods regularly, such as books, electronics, parts, wallets, documents, or textiles. They provide significant soft cost savings for big businesses, taking seconds to construct. When compared to book wrap mailers, they are 60% faster to pack and are used by Amazon due to this, leading to greater efficiency and productivity.

What products are these mailers suitable for?

This product is great for shipping anything that you would in a regular mailer, large letter postal box or book wrap mailer, including books, jewellery, photos, wallets, documents, textiles, electronics and wellness and beauty products. When expanded with box-like capacity, they can be used for a variety of small goods provided they fit comfortably.

Are M spec mailers environmentally-friendly?

These mailers have great eco-friendly credentials thanks to being made from corrugated material and are both 100% recyclable and biodegradable, aiding responsible disposal from the end consumer. They are the perfect sustainable alternative to traditional mailing bags.

What sizes are available?

M spec mailers are available in the following sizes: 257 x 229mm, 288 x 239mm, 320 x 279mm, and 350 x 324mm. Please note, these sizes are indicative of the their flat capacity. For full capacity, please refer to the product table.

Video: M spec mailers
How to use our envelope-like book mailers and our range of sizes

Our eco-friendly capacity m spec mailers are available in 4 popular sizes. These Amazon-style mailers are ideal for a range of small products! Either use them as flat, large letter cardboard envelopes or pop open the sides to make a small box. Then simply pop your product in and use our Peel-and-seal strip to secure. Once the customer receive the package there is a simple to use tear strip for the ultimate unboxing experience.

Standard mailers

Our simple yet effective standard capacity book mailers provide light to medium duty envelope-shaped protection for a range of book sizes and other products. Thanks to their 100% recycled and recyclable composition, made from 350gsm solid board, they are the ideal eco-friendly packing solution in which you can send your books, brochures, DVDs and more. Whether it’s a small diary sized book or a large hardback novel, there is a size for all.

Their slim, compact appearance makes them a highly presentable packing agent for businesses widespread. So if you would like to ensure high-quality protection for your books or other similar sized products, choose one of our eco-friendly capacity mailers today.

Premium mailers

Our premium corrugated capacity book mailers are the ideal strong, heavy duty, envelope-shaped protection for a range of different products. They are comprised of 100% recycled and recyclable carton material, making them a useful eco-friendly packing solution in which you can send your products. Each of our premium mailers features a micro F flute, making them puncture-resistant and ensuring a very high level of protection for a range of requirements. Due to this innovative design, they can prevent damage for items such as photos as they have a strong resistance against any bending that may happen in transit.

Their clear-cut, compact appearance makes them presentable packaging for businesses across a range of industries. So if you would like to ensure quality protection for your books, DVDs, photos, or other similar shaped products, choose one of our effective, strong capacity.


Video: Capacity book mailers
How to use our envelope-like book mailers and our range of sizes

Our eco-friendly capacity book mailers are available in a range of sizes. These envelope-style mailers are ideal for books, brochures, DVDs and other products with depth. Simply slip in your item and securely close using the peel-&-seal strip. Each size features an easy open tear strip making it simple for receivers to open the goods.