Want to get your hands on Google’s do-it-yourself Cardboard virtual reality headset? You can get it for free, but hurry before they sell out.

Cardboard is a virtual reality headset that uses your phone to create a VR experience with a simple and inexpensive setup: you fold the headset together, drop your phone in it, and it’s ready, according to a TechCrunch report. It’s like Oculus Rift, but a lot more basic, and it has been a side project for Google that will allow others to build upon it.

However, the clones typically cost about $20 to $30, not including shipping, a lot of money to spend on a chunk of cardboard, so OnePlus is going to give away a bunch of the clones for free as long as you pay the shipping, which costs about $5.

OnePlus’ clone is based on the Cardboard design, with some changes: thicker cardboard, a design that is 20 percent smaller, and a coating of dirt and oil resistant film.

The company said that while they aren’t making money by offering OnePlus Cardboard, it’s a marketing promotion that fits the brand’s messaging. By catering to the fanbase, they hope to make some new fans and promote their brand for the relatively low cost of a bunch of cardboard and plastic lenses.

Cardboard allows people who want the virtual reality experience but don’t want to pony up for Oculus Rift to still enjoy a more basic experience. The Cardboard model uses simple, low-cost components that are designed specifically for this purpose. Rather than assembling it, OnePlus provides users with the parts, schematics, and assembly instructions so they can build their own.

You can order them here: https://oneplus.net/cardboard#