Custom Fit for Universal Audio Apollo X4 Polycarbonate Shell Protects Machine from Dust and Grime Smoked Translucent Color The Decksaver Cover for Universal Audio Apollo X4 is designed to protect your Apollo X4 audio interface from scratches, dust, grime, and moisture. The cover is made from a lightweight and impact-resistant polycarbonate shell, and molded to precisely fit the device. It leaves room open for cables and can be kept on the device while it is transported in a flight case or controller bag.