The Aiphone Lef-3L Call Audio Master Station is a wired intercom system designed for indoor use. With 12 conductors and a wire length of 7,700 inches, this primary station offers a voltage of 12V DC and features a compact design with dimensions of 7 1/16 inches in height, 5 5/8 inches in width, and 2 1/8 inches in depth. It is suitable for use with the LEF Series and includes mounting hardware for easy installation. This product is backed by a 1-year manufacturer warranty and is designed to provide clear audio communication throughout a home or building.