Red sausage is a smoked Chinese sausage considered a regional specialty of Northeast China. It's sometimes known as a Harbin red sausage as it was probably first introduced in Harbin (the largest city in Northeast China). It is generally considered Russian in origin and known for its red skin and sports a more Western taste (it looks a lot like a Polish sausage) than other Chinese sausages.
The Red Sausage Pork Burger features two pork patties and a large slice of red sausage. The price comes to 21 yuan or about $3.47 US.
The Chestnut Grilled Chicken with Shrimp Sandwich features a grilled, flattened cut of chestnut grilled chicken with two breaded shrimp sticks. The shrimp-chicken combo is a little bit pricier than the sausage-pork at 27 yuan or about $4.46 US.
Chestnut chicken is typically a braised dish so it looks like they either braised the chicken before grilling or simply marinated it and then grilled it.
Both sandwiches are available through February 11, 2014.