Perfect size for my needs.
192 x 125 x 16mm White Superflat Large Letter Mailing Box B10
192 x 125 x 16mm White Superflat Large Letter Mailing Box B10 is a mailing and shipping package for structured protection and professional order fulfilment. Review the specifications and available variants below to confirm the required format, size and ordering quantity before purchase.
Choice of pack options: Select from 3 listed variants. The exact option name is shown at checkout, helping buyers match the required size, colour or quantity.
Paper-stream option: The source description identifies recyclable or recycled-content construction; dispose of it in line with local collection requirements.
Compostable construction: The original listing identifies compostable construction; follow the relevant local collection or composting requirements after use.
FSC-certified board: The original specification identifies FSC certification for the board used in this product.
Efficient assembly: The die-cut, tuck-front or self-locking format is designed for straightforward assembly and a tidy finished pack.
| Size / dimensions | 192 x 125 x 16mm; 192 x 125 x 16 mm |
| Colour | White |
| Material | Recycled kraft cardboard |
| Product reference | B10 |
| Available options | White / 192 x 125 x 16mm / B10 x100 | White / 192 x 125 x 16mm / B10 x200 | White / 192 x 125 x 16mm / B10 x500 |
| SKU reference | B010-100, B010-200, B010-500 |
| Product type | Mailing box / carton |
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Sizing
Inside: 192 x 125 x 16mm (length x width x height)










Order 1,000+ mailing boxes, or Australian-made shipping cartons by the pallet, and we'll quote a wholesale price. Trade accounts get invoice terms and a dedicated contact.
Superflat boxes are about 16mm high inside, made for flat items: art prints, cards, photos, stickers, scarves, folded t-shirts, books and documents. They protect corners better than an envelope and stay thin and light to post.
All sizes are internal (length x width x height), measured inside the box. The outside is a few millimetres bigger because of the board thickness.
Fold the box into shape, slide your item in, then close the lid and tuck the front flap into the front of the box. For extra security, seal the front flap with a strip of tape or a branded sticker.
Most superflat sizes come in white, brown, black, light blue and rose pink. Use the "Same size, other colours" link above the description to see every colour in this size.
Yes. The boxes are delivered flat in packs and fold into shape in seconds, so they take up very little shelf space.
Yes. We make custom printed boxes from 1,000 units, usually in around 2 weeks. Get a quote. For smaller runs, a printed sticker or stamp on a plain box works well.
The pack size is how many boxes come in one pack, for example x100 is a pack of 100 boxes. "Number of packs" sets how many packs you get, so x100 with 2 packs is 200 boxes.
Yes to both. We offer 90-day returns on unopened items (see our refund policy), and you can choose pickup at checkout and collect from Minto NSW or Braeside VIC, Monday to Friday 9am to 4pm.
Order online and we'll usually have it ready in 15–30 minutes at either warehouse.
Talk to our team
Call us on (02) 8750 5347
Fast delivery Australia-wide
Via Australia Post and trusted couriers
Pickup in Sydney & Melbourne
Minto NSW and Braeside VIC
90-Day Returns
On unopened items