FEFCO 0201 (regular slotted container / RSC) is best for you when you are shipping based on cost, volume, or weight; the auto-locking box (crash-lock / auto-bottom; in PT, automontável), when the bottleneck is packing or unboxing time. At TeleCajas, we have both in stock and also custom-made or with your logo, with no minimum order; we will ship it tomorrow, with free shipping from €50 on the mainland (ES and PT) and a flat rate of €50 to the Balearic Islands.
In Spain, "caja americana" (American box) is also a term for a picture frame. In packaging, it refers to the slotted cardboard box: 4 walls, 8 flaps, arrives flat, and is sealed with tape. If you store them flat and ship daily, start with our slotted boxes.
What FEFCO 0201 means
FEFCO 0201 is the European code for this box (RSC: Regular Slotted Container). If a B2B client asks for a "0201 double wall," they are asking for a slotted American box, not a mailer. The code does not determine strength: the wall type and grammage do. The wall type map is in corrugated cardboard.
American box vs. auto-locking box (crash-lock / auto-bottom / automontável)
The American box arrives flat and is sealed with tape on the top and bottom. The auto-locking box (also called crash-lock, auto-bottom, or in Portugal, automontável) is assembled by pressure: the bottom locks without tape and usually has a lid or quick-closure mechanism. They are not the same product; the common mistake is ordering a "0201" when what you actually want is a quick-assembly mailer.
Example of an American box: 20×15×15 cm slotted cardboard box. Example of an auto-locking box: small auto-locking postal box 18×10×9.4 cm.
When to choose which for e-commerce
Choose FEFCO 0201 / American if your order dimensions change, you are using pallets, it involves weight, or you need the lowest cost per unit and minimum volume stored flat.
Choose auto-locking if you assemble the same lightweight SKU many times a day, or if unboxing (clean lid, no tape on the bottom) is part of the experience. It costs more per unit; you recover the price difference in labor seconds.
| FEFCO 0201 (American / slotted) | Auto-locking (crash-lock / auto-bottom / automontável) | |
|---|---|---|
| Assembly | Form the prism and tape the bottom and top | Assembles by pressure; bottom locks without tape |
| Storage | Very flat; high storage density | More volume per unit; lower warehouse density |
| Cost / unit | Lower for same size and wall type | Higher; you pay for the time savings |
| Weight and pallet | Best for heavy loads or stacking | Designed for light / postal shipments |
| Unboxing | Functional; tape is visible | Cleaner and faster to open |
| When in e-commerce | Cost, volume, weight, variable sizes | Packing speed and opening experience |
Collections: slotted boxes (American) · auto-locking postal boxes.
How to assemble an American box
It arrives flat. You form the prism, seal the bottom with tape, load it, and seal the top. A poorly sealed American box fails at the base, not the walls. The secret is in how to tape a cardboard box. Accessory: adhesive tape. Size is about fit, not format: check liters in the same collection or the e-commerce box guide.
Frequently Asked Questions
Are FEFCO 0201 and "American box" the same?
Yes, in packaging: FEFCO 0201 is the code for the slotted American box (RSC). Do not confuse it with the picture frame, which in Spain is also called an "American box."
When to use auto-locking instead of American?
When assembly time or unboxing matters more than the box price: same lightweight SKU, many times a day. If you are weighing, palletizing, or changing sizes, stick with 0201.
What is crash-lock or auto-bottom?
These are names for the same type of auto-locking box: the bottom locks when assembled, without bottom tape. In Portugal, it is usually ordered as automontável.
Can I order American and auto-locking boxes with no minimum at TeleCajas?
Yes: both are in stock and also available custom-made or with a logo, with no minimum order. We will ship it tomorrow; free shipping from €50 on the mainland (ES and PT) and a flat fee of €50 to the Balearic Islands.
Does the FEFCO 0201 code indicate cardboard strength?
No. 0201 refers to the shape (flaps). Strength is determined by the wall (single/double) and the grammage. If someone asks for "0201 double wall," they are talking about this shape in more robust cardboard.
Next step: American boxes in slotted boxes (e.g., 20×15×15 cm) or quick packing in auto-locking boxes (e.g., 18×10×9.4 cm).
