Charging your devices wirelessly from across the room could soon become a reality thanks to ultrasound technology. UBeam, a small Los Angeles startup founded by Meredith Perry, 25, unveiled a fully working prototype of its technology on Wednesday, which will enable wireless charging just about anywhere.

Most wireless charging solutions currently require a device to be placed onto a mat to charge. But, uBeam’s solution takes that requirement out of the picture, enabling users to move around a room with the device while it continues charging. UBeam achieves this by converting electricity to sound and sending audio over ultrawave frequencies, where a receiver attached to a device captures the sound and converts it back into electricity.

The final uBeam charging transmitters will be as thin as 5mm, enabling users to attach them to walls or other location, the New York Times reported.

While uBeam could enable wireless charging within a room it does have limitations. UBeam doesn’t have the ability to pass through walls, requiring users to purchase multiple uBeam transmitters in order to enable charging throughout their entire home, Engadget reported. The company also hopes to also spur adoption of uBeam by offering the technology to both consumers and commercial venues. But at this time no release date has been announced for the technology.

UBeam is in the process of securing another round of funding, which tops an additional $1.7 million in funding from investors, including Yahoo Inc.’s (NASDAQ:YHOO) Marissa Mayer, Mark Cuban, the Founders Fund and more, according to CrunchBase.