Triplast 20 x DL White Self Seal Security Envelopes (Size: 110x220mm) | Fully Opaque, Self Sealing & Printer Safe Mailing Pap

Overview

Triplast 20 x DL White Self Seal Security is one of 49 envelopes & mailing products on our shelf, compared on what buyers rated it, how many of them there were, and what it costs today. Here is how the maker describes it: Pack of 20 White Plain Mailing Envelopes, SIZE: DL, LENGTH: 110 mm / 4.33 in, WIDTH: 220mm / 8.66 in, THICKNESS: 90 gsm, MADE in the UK. These envelopes feature a blue high security pattern on the inside that scrambles text to ensure contents remain concealed when in-transit or storage. That is the maker talking, not us, so read it as a claim rather than a finding. 2,019 ratings put it at 4.5 out of 5. The comparison with the rest of the shelf follows.

Shelf price range checked 29 Sept 2026, 06:33 BST · details

How it compares on the envelopes & mailing shelf

Across the 49 rated envelopes & mailing products we track, the middle of the pack sits at 4.6 out of 5. This one scores 4.5. That's inside the bottom quarter of the shelf. It isn't a warning, but better-rated options do sit alongside it at similar money, so you would want a specific reason to pick this one.

Behind that score sit 2,019 ratings, against a shelf median of 2,495. That's a solid enough base to read the score, though not enough to settle it.

Price-wise it falls in the bottom third of a shelf that stretches £1.20 to £29.99, with £7.99 in the middle. Buying at the cheap end is fine as long as the rating stands up. Here it does not quite, so check what has been cut before assuming the saving is free.

Shelf prices checked 29 Sept 2026, 06:33 BST · details

Worked out from the 49 envelopes & mailing products we track, not from the brand's own claims. How we rank →

Key features, as the manufacturer lists them

Taken from the product listing via Amazon's product API. These are the seller's claims, not our test results.

• CONTENTS: Pack of 20 White Plain Mailing Envelopes | SIZE: DL | LENGTH: 110 mm / 4.33 in | WIDTH: 220mm / 8.66 in | THICKNESS: 90 gsm | MADE in the UK
• ENHANCED SECURITY: These envelopes feature a blue high security pattern on the inside that scrambles text to ensure contents remain concealed when in-transit or storage. Send confidential documents with total confidence & peace of mind!
• HASSLE-FREE & PRACTICAL: The self-seal adhesive eliminates the need for any tape, glue or licking to seal these envelopes - just fold & press the top flap to secure shut! These envelopes are also compatible with most inkjet and laser printers.
• MULTIPURPOSE: These envelopes are ideal for mailing & organising invoices, letters, statements, catalogues, periodicals, brochures, etc. They are a cost-effective option for everyday home, office & commercial use!
• RECYCLABLE & PEFC CERTIFIED: Apart from being fully recyclable, these envelopes are made from paper sourced in a natural & controlled manner from SUSTAINABLY MANAGED FORESTS that also PROTECT THE RIGHTS OF WORKERS along the production process.

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