Flatpack

F3 Flatpack

352 x 249 x mm
In stock
Look no further for large letter flatpacks, the Lil F3 flatpack ensures the cheapest postal tariff every time. Maximising the large letter size limit and reducing your postal costs, these large letter cardboard envelopes are perfect for A4 sized brochures and other items. These large letter flatpacks are a seriously strong & professional packaging option for your e-commerce business. Fast to pack, tamper proof protection! For all Royal Mail Large Letter size mailers and small parcel postal tariff maximisers click here.  
1-9 £1.266 each (ex vat)
  • Weight79g
  • Qty box100
  • Qty pallet4050
  • 10+ £0.873 save 31%
  • 25+ £0.841 save 34%
  • 50+ £0.818 save 35%
  • 100+ £0.794 save 37%
  • 200+ £0.563 save 56%
  • 500+ £0.502 save 60%
  • 1000+ £0.437 save 65%
  • 2000+ £0.349 save 72%
  • 5000+ £0.337 save 73%
  • 10000+ £0.325 save 74%

Royal Mail Large Letter size mailers!

F3 large letter flatpacks for shipping A4 brochures, calendars and DVD's. Large letter cardboard envelopes. Are you looking for large letter size flat mailers to maximise the Royal Mail large letter size limit? You've come to the right place! If you're looking for something with more capacity, check out our C3 book wrap large letter postal wrap.

For all other Royal Mail Large Letter size mailers and small parcel postal tariff maximisers click here.

353 x 250 x 25mm is the maximum you can go to within Royal Mail Large Letter size. If you're using stiffeners, void-fill or airbags in your packaging, there is usually a better way to package what you're sending. For large envelope postage - the Lil F3 flatpacks are the best large letter cardboard envelopes, providing heavy duty packaging for delivering A4 brochures, calendars, DVD's, photos, photo frames, diaries, journals, arts & crafts and more through the postal system. The F3 is made from 150gsm 'Kraft' e-flute corrugated board; very stiff, tough stuff.  Every single flatpack in our range uses our leading hot melt peel'n'seal / red tear-strip system for easy sealing and easy opening.  Plus, like all of our postal packaging, they come with green credentials out of the box - 100% recyclable and FSC® certified / PEFC approved. Tough packaging doesn't get better than this! AusPost and Royal Mail Large Letter mailers - designed for cheap postal tariff mailings. Our sizes are extensively researched to get the snuggest fit - and lowest cost mailing tariff. If you're using stiffeners, void-fill or airbags in your packaging, the Lil F3 flatpack is a better way to package what you're sending. The Lil F3 is the stiffest envelope known to man!

Our tough large letter flatpacks are fast to pack because release paper overhangs the hot melt peel and seal flap. The hot melt adhesive peel and seal closure provides the best seal - at least twice the strength of standard double sided-tape.

Safe in transit but easy to open when it arrives. This really is tamper proof packaging.


Your packaging is the first time that your customers physically experience your product. Getting it right is your chance to make the best first impression. We help you do just that.

With a clear understanding of what you need, we use our knowledge and expertise to guide you to the most appropriate solutions. It's about delivering unrivalled service. Over 98% of our orders are dispatched within 24 hours.

Color Brown Corrugated
Flap Type Hotmelt Peel & Seal with red rip strip opening
Height 0
Glue Seams External seams
Internal Width MM 352
Width (mm) 301 - 400
Internal Length MM 249
Length (mm) 201 - 300
Height (mm) No
Internal Width Inches 13.7
Internal Length Inches 9.6
Item Thickness 150K E
Item Weight (g) 79
Pallet Size 100x120x165cm / 40x48x65"
Quantity per Box/Pack 100
Quantity per pallet 4050
Width 352
  • 100% recyclable

  • easy open tear strip

  • fits large letter

  • FSC® certified products

  • peel 'n' seal

  • supplied form strapped

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