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.

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.

Price

£39.09Save 15%

Reference price: ~~£45.99~~

Price checked: 12 Nov 2026

View offer

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Pros and cons

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.

Technical specifications

12 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

What to know before buying

Listing details to confirm

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.

Who is it for?

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.

ARPAN A3 Manilla Hardboard Envelopes, 457 × 324 mm, Pack of 100 · photo 2 — Additional product photo 2

Customer reviews on Amazon

4.7 / 5 · 603 ratings

5 stars81%81%
4 stars12%12%
3 stars4%4%
2 stars1%1%
1 star2%2%

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.
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.
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.