In the booming glass LED screen industry, the transparency is the most important factor for windows, this is why most of manufacturers try to make the highest transparency, Milestrong invisible PCB technology came out after many years development, this new technology not only expand the transparency rate up to 95%, but also can be made for any custom projects with soft PCB technology, you can also cut the size of film as you wanted easily.The STJ Series means the PCB board is also transparent, i