Google I/O attendees strolled out of yesterday's keynote with a simple cardboard kit that turns an Android phone into a virtual reality headset. It's part of an experimental Google service called Cardboard designed to create VR experiences inexpensively, and with hardware people already have. Even so, there's some work needed to make the headset, which — as the name implies — is a mix of cardboard origami, magnets, close-up lenses, and velcro. Google's offered up instructions on how to procure all this on your own, but isn't selling the kit it was giving out at I/O. Now another company has stepped in, offering the same thing at what it says is half the price.

Google's own suggestions for parts run $45

Dodocase, which makes protective cases for phones, tablets, and ebook readers, now offers a Google Cardboard VR Toolkit. It comes with a precut cardboard sheet, lenses, magnet, velcro, rubber band, and the option to tack on an NFC tag (which can be used to fire up the Cardboard app) for an extra five bucks. In an email to The Verge, Dodocase cofounder and CEO Craig Dalton said the company estimated Google's own parts list to run about $45, and coming from four different vendors. Dalton says the kits should be ready in 4 to 6 weeks.

Cardboard originated as a 20 percent time project from a pair of Google employees in Paris, and currently only has a handful of demos that let you explore Google Earth, Street View, and other Google properties with some makeshift stereoscopic imagery. It relies on an Android smartphone to split up the images, which are viewed through close-up lenses. What Google described as an "experimental" software development kit will also let developers build their own Cardboard apps.

Update June 27th, 2:32PM: Along with Dodocase, Knox Labs is selling two Google Cardboard kits. The cardboard version runs $18.95 (or $23.95 with an NFC tag). There's also an aluminum version in the works that will cost $65.95, or $68.95 with NFC.