The development phase comprised of many prototypes with varying sizes of batteries and connectors along with the positioning of buttons according to Willborn. The changes that have been made over the course of development have also resulted in the addition of an adjustable curvature in order to enable the device to connect to various kinds of helmets. The user interface has been brought down to a single button.
All that the users need to do is to connect the Tag with their phone or music player using Bluetooth 4.1. How does the gadget work? It makes use of transduction and fills the inside of the helmet with sound. Willborn says, “You can imagine Tag as a strong loudspeaker without any membrane. The tag uses the helmet itself as a membrane to create the sound.” The end result is a totally immersive experience with the vibrations being able to impart amazing bass tones.
It is made of thermoplastic polyurethane and measures in at 4.8×2.4in. It extends only 2cm out from the helmet and can survive speeds of up to 300km/h. It is water and shockproof and features a 600mAh li-ion battery that can last for 6-8 hours and is charged via USB port.