Mouse battery door missing. Microsoft Wireless Comfort Keyboard 4000 with Mouse & Transmitter 1045, 1008, and 1028 is a sleek gray keyboard and mouse set that offers ergonomic support for comfortable typing and navigation. The keyboard has a wireless connectivity option for convenient use without the hassle of cords. With the brand being Microsoft, you can trust the quality and reliability of this keyboard set, perfect for everyday use on your computer or tablet. The set includes a keyboard with English language support and ergonomic features, making it a practical and comfortable choice for any user.