What are our letterboxes made from?

What are our letterboxes made from?

At Heatlie Letterboxes we take pride in the fact that all our letterboxes are made right here in Australia at our North Plympton, South Australia factory. Sharing a factory with Heatlie BBQs, we have access to a diverse range of materials, tools and tradespeople to ensure we manufacture the best possible letterboxes for our customers. 

We have a strong focus on creating products that last, which means we always use high quality materials, that go through all the proper procedures to make sure you aren't having to replace your letterbox (or BBQ) a year down the track. 

Here is a breakdown of the materials we use to construct our letterboxes.


The majority of our product range is made from aluminium sheet that we cut, fold, chromate treat and powder coat.

We use a variety of thicknesses but we use 3mm thick aluminium for the letterbox doors and other important structural parts as it is nearly impenetrable. It can't be easily folded or bent as some traditional 1.6mm thick aluminums can. This means vandalism and break in attempts are much harder on your letterbox. 

Aluminium does not rust but it can corrode. The chromate treatment acts as a corrosion inhibitor to protect the letterbox from ever corroding. This, with a nice thick, smooth layer of powder coat will have your letterbox lasting for decades. 

We powder coat all our own letterboxes in house with our trusty powder coating oven. The powder is baked on at high temperatures and comes out looking spick and span. 

The four walls of the letterboxes are fixed together using pop rivets for ultimate structural security. Faceplates are fastened on by clamping them together with the box with very-high bond double sided tape. All this together means that once your letterbox is fixed in its place in your fence or wall, it's not going anywhere.

Stainless Steel

We use stainless steel for a small handful of letterbox products such as custom faceplates and numbers. It is of 304 grade and will evade the effects of corrosion as long as it is polished, cleaned and generally looked after. Our stainless steel is 1.6mm thick for a strong and unbreakable build.

Galvanized Steel

The thickest and strongest build of all, we use galvanized steel for just one letterbox, the Vandal Resist. It's built like a tank and carries a lot more weight to it because of this. 

Our Installation Channels are also built from galv for extra structural security when installing a letterbox in a wall or gabion fence.


One of our numbering options is a vinyl print out that is stuck to your letterbox. The vinyl is thin and smooth, but don't be mistaken it is still heavy duty and rated for outdoor use. It's similar to that which you see stuck on cars for branding. It provides a modern, sleek look for your numbers and you can play around sufficiently with colours and fonts.

Got any questions about how our letterboxes are made and what they are made of? We're always here to help!

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