Polythene Mailers - Grey 250G
White Co-Ex Opaque Poly Mailers (A4-Friendly) — Secure, Professional Postal Packaging
These white co-extruded (Co-Ex) opaque poly mailers are designed for fast, reliable dispatch of documents and lightweight goods where privacy, presentation, and weather resistance matter. The bright white outer layer gives a clean, professional look for ecommerce and business mailings, while the opaque construction helps conceal contents during transit. With an A4-friendly format and a practical sealing flap (lip), they’re a dependable choice for daily packing benches, mailrooms, and fulfilment operations.
Poly mailers are a popular alternative to paper envelopes and boxes for non-fragile items because they are lightweight, space-efficient, and quick to seal. This style is especially useful when you want a neat, uniform parcel appearance and a packaging solution that helps protect against rain splashes, scuffs, and handling marks commonly encountered in postal networks.
Key Features
Co-Ex multi-layer film:
Co-extruded film uses multiple layers to balance toughness and flexibility. This helps the mailer resist tearing and punctures from typical handling while remaining easy to pack and seal.
Opaque white finish for privacy:
The opaque construction is intended to reduce visibility of the contents, supporting discreet shipping for clothing, paperwork, and other items you’d rather not display through the packaging.
A4-friendly capacity:
Suitable for A4-sized documents and flat items, making it a practical option for invoices, paperwork, catalogues, and many common ecommerce orders.
Sealing flap (lip):
The integrated flap provides a straightforward closure area for secure sealing and consistent packing speed—ideal for repetitive dispatch tasks.
Lightweight to help control postage costs:
Compared with rigid packaging, poly mailers add minimal weight, which can help keep shipping costs predictable—especially when sending high volumes.
Clean, professional presentation:
The white exterior supports a tidy brand appearance and is well suited to applying labels, barcodes, and shipping documentation.
Space-saving storage:
Supplied flat, these mailers store efficiently and are easy to keep at hand on a packing station without taking up the space required by boxes.
- Co-Ex opaque film for privacy and a premium look
- A4-friendly format for documents and flat goods
- Practical sealing flap for quick, consistent closure
- Lightweight packaging to support efficient shipping
- Flat-packed for easy storage and fast picking
Typical Uses
- Clothing and soft goods (t-shirts, leggings, scarves, accessories)
- Documents and paperwork (A4 sheets, letters, invoices, statements)
- Printed materials (brochures, leaflets, catalogues, magazines)
- Non-fragile ecommerce orders where a box isn’t required
- Returns packaging for apparel and lightweight items
No1 229×320 + Lip White Co-Ex Opaque Poly Mailers — Full Product Guide
Choosing the right mailer is about balancing protection, presentation, and packing speed. This guide explains what co-ex poly mailers are, how they perform in real-world dispatch, and how to decide if they’re the best fit for your products and workflow.
How It Works
A poly mailer is a flexible mailing bag designed to hold items securely while keeping the parcel lightweight. You place the item inside, remove excess air for a flatter profile (where appropriate), and seal the flap. Once sealed, the mailer forms a protective outer layer around the contents, helping to shield against moisture and surface abrasion during transit.
Because the bag is flexible, it can conform to the shape of soft items, which often reduces wasted space compared with a box. This can be helpful for postage bands that consider parcel dimensions as well as weight.
Materials and Construction
Co-extruded (Co-Ex) film: Co-ex film is produced by combining layers during manufacture. In practical terms, this can provide a useful blend of strength and usability—helping the mailer resist tearing while still being easy to handle at speed.
Opaque white outer: The white exterior is designed for a clean appearance and to support privacy. Opaque mailers are commonly chosen when you want to reduce the chance of contents being visible through the packaging.
Thickness (micron): This product is specified at 55 micron. Micron thickness is one indicator of film robustness; in general, thicker films can offer improved resistance to punctures and tearing, though overall performance also depends on the film formulation and construction.
Floor Type Compatibility (Packing Environment)
These mailers are suitable for a wide range of packing environments:
- Warehouse fulfilment: Easy to pick, open, insert, and seal at a bench.
- Retail back-of-house: Useful for click-and-collect dispatch and returns processing.
- Office/mailroom: A practical option for sending A4 paperwork and flat items.
For best results, keep mailers in a clean, dry area near your label printer and tape/sealing supplies so packers can work in a smooth sequence: pick → pack → seal → label → dispatch.
Health and Safety
As with all plastic packaging, keep poly mailers away from babies and small children due to suffocation risk. In a workplace setting, store cartons safely to avoid trip hazards and ensure cutting tools (if used for opening cartons) are handled in line with your site’s safety procedures.
Ideal Applications and Use Cases
Apparel and textiles: Poly mailers are a strong match for clothing because garments are typically non-fragile and benefit from a lightweight, water-resistant outer layer.
Paperwork and printed materials: The A4-friendly format makes these mailers convenient for sending documents and flat printed items that you want to keep clean and presentable.
Subscription and repeat shipments: If you ship similar items repeatedly, standardised mailers help create consistent packing times and a uniform parcel appearance.
Returns: Many businesses include a mailer for returns or use mailers to process inbound returns quickly. A consistent mailer size can simplify your reverse logistics workflow.
Maintenance, Cleaning and Care
Poly mailers require minimal maintenance. To keep packing efficient:
- Store flat in the original carton to prevent creasing and contamination.
- Keep away from excessive heat and direct sunlight to maintain film condition.
- Use clean hands or gloves in packing areas where presentation is important.
- Apply labels to a smooth area of the mailer for best adhesion.
Case Study (Practical Packing Workflow)
Scenario: A small ecommerce clothing brand dispatches daily orders containing one or two garments plus an invoice.
Challenge: They want a professional-looking parcel that protects against rain and handling, without the cost and storage space of boxes.
Solution: Switching to white opaque co-ex poly mailers standardises packing. Staff insert the garment, add paperwork, seal the flap, and apply a shipping label. The result is a consistent, discreet parcel that’s quick to pack and easy to store in bulk.
Outcome: Faster packing at peak times, reduced storage footprint, and a cleaner presentation on delivery.
Who Is It For?
- Ecommerce fulfilment teams shipping soft goods and non-fragile items
- Retailers needing reliable mailers for online orders and returns
- Offices and mailrooms sending A4 paperwork and printed materials
- Subscription businesses looking for consistent, repeatable packaging
Colours / Features Available
This listing is for white opaque co-ex poly mailers. Co-ex mailers are commonly offered in different colours and finishes across ranges; if you need an alternative colour or a different style (for example, other mailing bag types), browse the relevant category to compare options.
Sizes Available
This product page may represent a configurable range. Select the size/variant that matches your packing needs. When choosing a mailer size, allow room for the contents plus any paperwork, and consider whether you want a snug fit (neater parcel) or extra space (easier insertion and sealing).
If you regularly ship multiple item types, consider standardising on a small set of mailer sizes to simplify stockholding and speed up packing.