Inner box and master carton formats
By Mohamad Sinno, Charcoal Expert · published .
Ask AI for an importer brief:
The short answer
Five cube sizes have measured inner-box dimensions. Four master cartons have measured dimensions. Every other shape's inner box is made to order and has never been written down, so those cells say so rather than carrying a plausible number.
Inner boxes, 1 kg
| Shape and size | Inner box, mm | Board and print |
|---|---|---|
| Cube 22 mm | 97 × 81 × 186 | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Cube 25 mm | 105 × 80 × 157 | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Cube 26 mm | 111 × 111 × 111 | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Cube 27 mm | 170 × 88 × 88 | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Cube 28 mm | 119 × 88 × 120 | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Cube with hole (26, 30 mm) | Not recorded — ask the export desk | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Hexagonal, stix, octagonal (20×50, 20×35, 21×50, 22×50, 22×35 mm) | Not recorded — ask the export desk | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Flat / brix (25×25×15, 25×25×17 mm) | Not recorded — ask the export desk | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
| Dome (20×35 mm) | Not recorded — ask the export desk | 1 kg inner duplex 250 gsm E-flute, varnished, CMYK |
Four rows in that table are empty, and they are the most useful rows in it. Our data sheet records inner-box dimensions for the five cube sizes and states, in terms, that the non-cube sizes are not recorded and must not be inferred. We could halve a cube figure, or scale one by the piece dimensions, and produce five numbers that looked exactly as authoritative as the measured ones. A buyer ordering a dieline against an inferred dimension finds out at the print run.
The board and print column is filled for every row because the material spec does not change with the shape — it is the dimensions that were never measured, not the carton construction.
Master cartons
| Master carton | Dimensions, mm | Board and print |
|---|---|---|
| Cube 25 mm | 415 × 217 × 164 | 10 kg master kraft K150/M125K150 B-flute, up to 3 colours |
| Cube 26 mm | 560 × 225 × 115 | 10 kg master kraft K150/M125K150 B-flute, up to 3 colours |
| Cube 28 mm · 20 kg | 478 × 258 × 281 | 10 kg master kraft K150/M125K150 B-flute, up to 3 colours |
| Cube 28 mm · 10 kg | 478 × 258 × 90 | 10 kg master kraft K150/M125K150 B-flute, up to 3 colours |
Two of those rows carry a net weight and two do not, and that is the sheet's own shape rather than an omission here: a 20 kg master exists for cube 28 alongside the 10 kg one, so those two rows are labelled to tell them apart. Writing "10 kg" onto the cube 25 and 26 rows would be transcribing an inference as though it were a measurement.
What fits in a container
The format decides the count; the count decides the payload. These are measured loads for the standard boxed packing:
| Shape | 20 ft | Cartons | 40 ft | Cartons | Counted? |
|---|---|---|---|---|---|
| Cube 25 mm, 26 mm | 20 t | 2,000 | 26.5 t | 2,650 | Counted at packing |
| Cube 27 mm, 28 mm | 19.5 t | 1,950 | 26.5 t | 2,650 | Counted at packing |
| Hexagonal, stix, octagonal, flat/brix | 18.5 t | 1,850 | 26.5 t | 2,650 | Derived |
| Dome | Not measured | — | Not measured | — | Not measured |
The last column is there because two of those rows were physically counted at packing and one was arrived at by arithmetic — and a reader deciding how much to trust a figure deserves to know which. The dome row is blank throughout: the shape is pressed, no dome load has ever been measured, and the sheet forbids inferring one.
The code that ties a carton to its batch
Every master carton carries a four-digit batch production code, two letters identifying the packing team, and one check digit. The batch code identifies the production batch whose QC file holds the laboratory COA and the factory’s own results. Inner-box marking: not recorded. That last point matters when a carton is opened and the inner boxes are distributed — the traceability lives on the outer, so a repacked inner box does not carry it with it.
Choosing between the formats rather than looking one up is the job of the packaging overview; what bulk and neutral do to price is at bulk and neutral packaging; and if the box is going to carry your own artwork, the lineup decision is at OEM packaging formats and weights.
Need a dimension that is not here?
Ask the export desk for the shape and size you are packing. The non-cube inner boxes are made to order, so the answer is a real measurement rather than a table lookup — send the spec and it comes back with the carton it fits.