Walmart offers the Microsoft Surface Dock for Surface Pro 3, 4, or Book, model no. PD9-00003, for $124.99 with free shipping. (For Prime members, Amazon charges the same.) That's tied with our mention from two weeks ago as the lowest total price we've seen. (It's also the best deal now by $24.) The dock acts as a charger and features two mini DisplayPorts, Gigabit Ethernet, four USB 3.0 ports, and audio jack.