Self-Locking Mailer Box Dieline Template - ECMA A10.20.03.01

The Self-Locking Mailer Box (ECMA A10.20.03.01) is a simple and tough one-piece box that’s really good for e-commerce packaging, subscription boxes, retail shipping, and just about any product mailer. It’s built to fold quickly, lock tight, and doesn’t need any glue or tape, which saves both time and money. Small brands or big factories can both use it without much trouble.

It follows the ECMA A-Series standard, so the layout comes out accurate for cutting and folding. With PackMyMan, you can make your own size and download the dieline instantly in SVG, DXF, or PDF formats, ready for your printer or production team.

What Is ECMA A10.20.03.01
This design belongs to the ECMA A-series, which is made for manual or half-automated packaging jobs. It’s often called a self-locking or snap-lock mailer, because when you fold the panels down, the tabs hook in and hold everything together on their own.

There’s no need for glue, since the board locks itself once you shape it correctly. The box stays solid, and it doesn’t pop open even during rough shipping.

Main Benefits of the Self-Locking Box

Here’s why people use it a lot:

• Assembles quickly, just a few folds and the box holds its shape.

• Tabs and slots add strength, keeping items safe during delivery.

• Made from one flat sheet, so there’s less waste and faster cutting time.

• Custom fit with PackMyMan, so products don’t rattle around inside.

Because it’s all one piece, this style works well for quick runs, subscription orders, or any place where people are packing boxes by hand.

Common Uses

The ECMA A10.20.03.01 mailer box is seen all over the place now:

• Online store packaging

• Monthly subscription boxes

• Launch kits for products and influencers

• Corporate or brand merchandise boxes

It’s neat on the outside and holds up well — a good balance between simple design and reliable build.

File Formats and Options

In PackMyMan, you can download the dieline as:

• SVG for design or CNC cutting

• DXF for CAD and laser cutters

• PDF for proofing and print sharing

All files come with clear cut and fold lines, so there’s no confusion during setup.

Designed for Production

Every part of the design — creases, flaps, alignment — is made with real-world printing and die-cutting in mind. It works with most board types like kraft, duplex, or coated stock, depending on what you need.

Printers like it because setup is quick and boxes come out uniform on each run.

Why It’s Still a Favored Packaging

Even though there’s fancy packaging out there, the Self-Locking Mailer Box (ECMA A10.20.03.01) stays popular because it just works. It’s easy, costs less to produce, and makes shipping clean and professional.

If you need packaging that’s simple, solid, and quick to assemble — this is one of the best options to go for.