The GridFusor™ is manufactured in Europe to tight tolerances for excellent performance at a reasonable price. It's equally at home in a home studio or listening room as it is in a professional studio, editing room, or auditorium. It has a usable range of 600Hz to 7.5kHz. GridFusor™ are made from EPS (expanded polystyrene) so they are light enough to be easily mountable on walls, ceilings, etc. without the use of damaging adhesives or massive mounting holes while still providing excellent diffusion characteristics.