Rigid board backHelps resist bending
125 strong A4 envelopes per box
Keep important A4 documents flat, clean and protected.
Strong C4 manilla envelopes with a rigid board back and a clear “Please Do Not Bend” warning — ideal for certificates, photos, artwork and business documents.
4.7 out of 5
from 208 reviews
Box price
£30
24p per envelope
A4 / C4 size324mm × 229mm
Printed warningPlease Do Not Bend
Fast UK deliveryFree next day over £100
Rigid backing helps documents arrive flat and presentable
Box of 125
125 × A4 manilla board backed envelopes
A dependable postal envelope for documents that should not be folded, creased or damaged in transit.
One box of 125
£30
24p each
- External size
- 324mm × 229mm
- Fits
- A4 sheets without folding
- Colour
- Brown manilla
- Front print
- Please Do Not Bend
- Box quantity
- 125 envelopes
Spend over £100 before 10am for free next-day delivery.
Built for safer posting
Simple protection that makes a professional difference
Use a rigid-backed mailer when presentation matters and ordinary paper envelopes are not enough.
Helps prevent creases
The rigid backing supports flat documents and reduces the chance of unwanted folding during handling.
Looks more professional
Documents arrive flatter, neater and ready to present — useful for customer orders and important paperwork.
Made for valuable contents
A practical choice for photographs, certificates, prints, artwork, reports and other A4 items.
One envelope, many uses
Ideal whenever “do not bend” really matters
From everyday business post to one-off important documents, the firm backing adds a useful layer of protection without requiring a box.
Choose your quantityCertificates and legal documents
Photographs and printed artwork
Presentations and client proposals
Reports, brochures and catalogues
eBay, Etsy and online shop orders
Important personal paperwork
“Fantastic envelopes — really good quality and fast delivery as well.”
4.7
out of 5
208 reviews
Secure online order
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Questions answered
Everything you need to know before ordering
The essentials about size, quantity, delivery and payment.
Will A4 sheets fit without folding?
Yes. Each envelope measures 324mm × 229mm, giving standard A4 sheets enough room to be posted flat.
How many envelopes are supplied?
Each box contains 125 brown manilla board backed envelopes.
What is printed on the front?
Each envelope is clearly printed with “Please Do Not Bend” to help postal handlers identify the contents as bend-sensitive.
When is next-day delivery free?
Free next-day delivery applies when the order is placed before 10am and the product total is over £100.
How is payment taken?
The order is created and captured through PayPal. Your final total is recalculated and verified on the server before payment is accepted.
Ready to protect your post?
Start your order
Order 125 A4 board backed envelopes for £30.
Strong, simple protection for documents that need to arrive flat.