C4 / A4 Board Backed Envelopes with Stiffeners (324 × 229 mm) — Bulk Rigid Mailers x 1000

C4 / A4 Board Backed Envelopes with Stiffeners (324 × 229 mm) — Bulk Rigid Mailers x 1000

£179.50 Inc VAT: £215.40

SKU: BBENV-C4-BR-EWS#1000 Categories: ,

Description

Deliver your large, flat items with confidence using our C4 / A4 board backed envelopes with stiffeners. These are hard backed envelopes enhanced by included corrugated board stiffeners, giving extra protection without significantly increasing postage weight. This listing is for bulk quantities, providing excellent value and consistent supply for businesses, print shops, galleries, e-commerce sellers, and high-volume mailers.

Features & Construction

  • Dimensions: 324 mm × 229 mm (12.75″ × 9.0″) — large enough to accept A4 documents without folding. Defenda Packaging

  • Envelope build: Made with 120 gsm paper shell over a 600 gsm or 1000 micron backing board. Defenda Packaging

  • Stiffener: Includes a strong E-Flute corrugated board stiffener measuring ≈ 310 × 215 mm, which sits inside the envelope to reinforce rigidity. Defenda Packaging

  • Weight / Postage class: Approx. 84 g (with stiffener) — classified as Large Letter under UK postal rules. Defenda Packaging+1

  • Packaging / quantities: Available in multiple bulk packs (e.g. 50, 125, 250, 500, 1,000 units) to suit your volume needs. Defenda Packaging

  • UK manufactured: Made domestically, with recyclable materials, reducing import miles. Defenda Packaging

  • “Extra Strong / Ultimate Protection” labeling: Emphasises that this is a more robust option for fragile flat mailings. Defenda Packaging

What Fits Inside & Use Cases

With the combination of board backing + stiffener, this envelope can protect and deliver a variety of flat items:

  • Flat A4 documents (reports, proposals, artwork, contracts) with no folds

  • Artwork, drawings & prints (including mounted or thick stock, up to limits)

  • Certificates, diplomas, portfolios

  • Magazines, catalogs, booklets (if thickness and weight permit)

  • Photographs or framed prints (thin-mounted)

  • Marketing packs, sample sheets, promotional literature requiring backbone

The stiffener acts like internal scaffolding, resisting bending and ensuring the contents remain perfectly flat even under postal handling.

Why Bulk Orders Are Ideal

  • Better unit economics — the more you buy, the lower the cost per envelope

  • Consistent inventory — maintain stock for regular mail campaigns without delays

  • Quality consistency — all envelopes meet the same specifications

  • Fulfillment efficiency — pack, store, and ship more effectively at scale

Benefits to Your Customers

  1. Max protection: The dual structure (backing + stiffener) guards against bending, creasing, and postal damage.

  2. Professional delivery: Recipients receive high-value print items flat, pristine, and impressive.

  3. Postal-savvy design: Though robust, the construction aims to stay within beneficial postage classes (Large Letter) where possible.

  4. Versatility: Useful for high-stakes mailings — artwork, important documents, presentations.

  5. Bulk-ready: Supplier packaging is suited for business usage — stackable, consistent, reliable.

Related products