About this item Material: durable plastic, copper and gold-plated metal. Cutout diameter: 2.95'D; Overall diameter: 2.95'W; Top-mount depth: 1.77'H. Terminal cup for speaker subwoofer boxes. Gold-plated contacts for optimal signal transfer. Screw terminals ensure a tight and secure connection. Rear connections use quick disconnect connectors. Positive (Red) and negative (Black) indicators to ensure proper wiring. Dimensions: 2.95'D x 2.95'W x 1.77'H.