These are Virtual Reality goggles for use with your mobile phone. For full customization, you can get the full OpenSCAD source code and detailed build instructions here; https://github.com/secondsight/secondsight-hardware/From https://github.com/secondsight/secondsight-hardware/blob/master/README.md Preparing to Build a Headset There a few pre-requisites that you need to build the secondsight headset from this project. Lenses Head strap 3D printer Android phone Open cell foam or neoprene Lenses We have had reasonable luck with lenses in the 25mm to 37mm diameter range, with a focal length of 50mm. The field of view is directly related to the diameter of the lens. A 35-37mm diameter lens seems to give a view that covers the whole phone at this focal length. A 25mm lens doesn't quite cover the whole phone. We have tried as high as 50mm diameter. That lens had a field of view larger than the phone and required a larger visor design. The current design is currently set for the 36mm Lens from B&L 5X Aspheric Pocket Magnifier. We will be releasing our own pcx lens designs soon. Head strap While you could use the headset by holding it to your face with your hands, this would get old really quick. The headset is designed to use a 40mm wide elastic strap to hold the headset. This gives good support without requiring an extremely tight fit to avoid slipping. 3D Printer You should be able to use any 3D printer with a large enough build volume. The visor has been successfully printed in both ABS and PLA. Android Phone The current visor design is optimized for the Galaxy S4 phone. The design does not require exactly that phone, but it the front of the visor was designed around the dimensions of the S4. It has been used with different phones that are close to the same dimensions (e.g. Galaxy Nexus). Open Cell Foam or Neoprene The hard plastic is mildly uncomfortable fitting directly against your face. It's not painful, but it is hard plastic supporting a phone. A small amount of foam applied to the back side of the visor makes the fit much more comfortable. A cheap source of reasonable material is a cheap mousepad. You can easily cut pieces to fit the visor.