# ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100

Hardboard: ARPAN A3 Manilla Hard Board Back Envelopes are flat, self-sealing mailers with a fibreboard backing and a printed “Do Not Bend” message. The stated A3/C3 size and 100-pack suit regular dispatches of artwork, photographs and documents, though customer feedback is mixed on sturdiness and adhesive strength.

- [Original product page](https://bargainpostbox.co.uk/product/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [View offer](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- Market: UK
- Language: en-GB
- Currency: GBP
- Brand: ARPAN
- Category: Office & Stationery > Packaging & Shipping Supplies
- Price: 39.09 GBP
- Previous price: 45.99 GBP
- Discount: 15%
- Price checked: 2026-11-12T15:02:25.445Z
- Rating: 4.7 / 5
- Reviews: 603

Prices and deal status are the latest recorded data, not a guarantee of availability. Confirm the price and availability with the store.

## At a glance

- A3/C3 format measures 457 × 324 mm according to the listing.
- The listing describes a rigid board backing and a printed “Do Not Bend” message for flat documents and prints.
- Self-seal closure avoids the need for separate tape, according to the product description.
- The listing says the envelopes are made from recycled materials.

## Pros

- Pack of 100 suits repeated A3 mailing or document storage.
- Self-seal closure is designed for quick packing without separate adhesive.
- The board-backed format and printed handling message are intended for flat artwork, photographs and documents.

## Specifications

### Identity and format
- Brand: ARPAN
- Style: Flat
- Shape: Rectangular
- Size: Pack of 100
- Item dimensions: 45.7L x 32.4W centimetres
### Materials and protection
- Material listed: Fibreboard
- Colour: Kraft \(light brown\)
- Printed marking: Printed: Please Do Not Bend
### Closure and use
- Closure type: Self-Seal
- Special features: Lightweight, Self Seal
- Recommended use: Letter
- Occasion: everyday mailing

## Before you buy

- Customer feedback reports mixed views on sturdiness, with some describing the envelopes as flimsy, and mixed views on adhesive strength. The listing claims a strong self-seal strip, but that claim does not settle those differing experiences.

## A good fit for

- People regularly mailing A3 artwork, prints, photographs or documents.
- Offices, schools and small businesses that want a 100-pack of board-backed envelopes for mailing or organisation.

## Less suited to

- People needing a confirmed level of impact, moisture or tamper protection, which the supplied listing does not establish.
- Buyers who need consistently rigid construction or a predictable seal based on customer feedback.

## Customer feedback

Customer feedback highlights positive impressions of quality, size, functionality and value, with some customers saying the envelopes fit their documents and do the job well. Sturdiness and adhesive strength receive mixed feedback, including descriptions of the envelopes as flimsy and comments that the seal is very strong. For buyers sending flat A3 items, this means the listed size and self-seal design may be useful, but the listing claims of rigid backing and a strong seal should not be taken as proof of uniform customer experience. Aggregate ratings are broadly positive, but they do not explain individual experiences.
- Positive themes: Customers describe the envelopes positively for quality and size, and report that they do the job well.
- Positive themes: Some customer feedback describes the adhesive as very strong.
- Mixed feedback: Customer feedback is divided on sturdiness, with some finding the envelopes sturdy and others describing them as flimsy.
- Mixed feedback: Adhesive strength receives mixed feedback.

## Frequently asked questions

### What size are these envelopes?
The listing identifies them as A3/C3 and gives a size of 324mm x 457mm \( A3/ C3 \). It also lists item dimensions as 45.7L x 32.4W centimetres.
### How many envelopes are included?
The title and size details describe a pack of 100.
### Do they have a self-seal closure?
Yes. The listing specifies a self-seal strip. Its claimed adhesive strength is not consistent across customer feedback.
### Are they suitable for photos and artwork?
The listing recommends them for artwork, prints, photographs and documents, with board backing and a printed “Do Not Bend” message. It does not establish a guaranteed level of protection in transit.

## Alternative options

- [20x C3 / A3 Manilla Hard Board Back Envelopes - 457x324 mm - Cardboard Backed Please Do Not Bend Envelope with Peel & Seal Strip - Perfect for Mailing, Posting & Storing Important Documents](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [Double Dragon 100-Pack A4 C4 Manilla Hard Board Backed Envelopes \| 324mm x 229mm \| 'Please Do Not Bend' Printed \| Padded & Tamper-Proof \| Self-Seal Closure](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [UKPAPER 100 x Please Do Not Bend Envelopes A3 / C3 457mm x 324mm Hard Back](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
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- [250PCS 229mm x 162mm A5 C5 Manilla Hard Board Backed Envelopes Please Do Not Bend Right Pack \(Box Pack of 250\)](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [STRBOXONG A4 Hardback Envelopes Do Not Bend, C4 Hard Board Backed Envelopes Peel and Seal for Art Prints & Certificates, Brown Manilla Cardboard Mailers, 324 x 229mm, Royal Mail Large Letter\(10 Pcs\)](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [JeeJaan® 36 Rolls of Clear Parcel Tape of 48mm x 66m Heavy Duty Plastic Packaging Tape for Shipping Cartons Box Packing Warehouse Moving House and Secure Parcel Sealing](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [100 Pack A3 Hard Backed Envelopes C3 Please Do Not Bend Card Envelopes \| 458mm x 324mm Brown Manilla Strong Envelopes](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)

## Add-ons

- [ARPAN A4 Manilla Hard Board Backed Envelopes \(324 x 229mm\) – A4 Do Not Bend Mailers with Self Seal Strip \| C4 Rigid Cardboard](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)
- [20Pcs A4 Envelopes Self-Seal iSOUL 324mm x 229mm A4 C4 Manilla Hard Board Backed Envelopes Do Not Bend Envelope](https://bargainpostbox.co.uk/visit/arpan-a3-manilla-hardboard-envelopes-100-pack)

## Images

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 1](https://bargainpostbox.co.uk/i/EtTxSfDbv_qxo4Jio3FkiikUV36m6yitUDeoEgd28LBxak_2RDs_r0SliWmLd7URAvzh5qkkf57OAoH6GYIHMD6U1lRC096E-aOLZPRpBN2l1d8F0wgzux9_.jpg)

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 2](https://bargainpostbox.co.uk/i/nTSkTTzMpmKZQaGBHCHlCK9y-umfvHT9t9WOuAmR5BEy0CFr_RHpeDCR6REmQOD-5B29ESRaoZetqP0t6G9d5SQO17Vn29j8dY1TTF2aKyxaXdDeLWBXmk6T.jpg)

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 3](https://bargainpostbox.co.uk/i/5hlviiC3dAj4nsQgo2KgOVQMAN4jZgItf2ZhzNCWaVuu0vw-FqkxmWZu5OTGQR9RxOB4x59Ky1y2sr3D-0s0Y20a6F9VGklWMRiwbjNFVQmqsNZQF34CKbdZ.jpg)

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 4](https://bargainpostbox.co.uk/i/0h7XV4xv6423RWb-ZB3sucFpt4d52lsX5ZTqsXi90lfxOPXaMnmtBVEc4tum5bR8cNTNxgBmGFWMnAsBhdYoGVbFTZRx_j5OIrzEvd0upsKDs6qX8_a08Ty-.jpg)

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 5](https://bargainpostbox.co.uk/i/qKjHoiXYiCEA6utagvOZ4iBXW6QUpHF5kW7RdvQ7RwkSUSAMeiqCIDgsOtwQdW1vc5-7sSLuyTezFVURP0J4eVCIvtbHzSoi5TNadTltrSKMWh003O6zdcG_.jpg)

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 6](https://bargainpostbox.co.uk/i/zKwsLOEF1k7dQbAZxEgMvJUYpIMkQs4AUbivlq4SDc-Cvu5hC8TCHB6KTxmXW7oWkAgb2DLeHC5rdnNBFSDBN5OGehujWEBWLi6NuRmX4AxRNnQNJtgnBCBo.jpg)

![ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 — 7](https://bargainpostbox.co.uk/i/tvCN1jZquN48cmarR2HEJMtrH85a3wyy1gZMiM03feeUv2zr4Kq9bapRs-Zh8_UTtB9OQrbGaoLDWvY4Rf-5SrT4GmCBc6MimIpBrT1Qa37j29Vp1IHJut8t.jpg)