This is the popular advanced trainer that was sold by Great Planes. Span is 65 inches. It is similar to the RCM Advanced Trainer, also known as the RCM Trainer. Both planes have a thick symmetrical airfoil and are essentially a high wing constant chord version of the Kaos. The major difference is that the RCM version has a single elevator, but the Great Planes version has split elevators. Because of this detail, the Great Planes version is easier to convert to tailwheel configuration.
Download the original Great Planes Trainer 60 plan for this kit, not the more recent CAD version, because the CAD version has inaccurate dimensions on most of the parts.
The kit is supplied with the thick rib as shown on the plan, which the instructions say you are supposed to sand to a taper and place between the two wing halves for dihedral. The kit also includes a dihedral gauge so you can set the root rib on each wing panel to produce the correct dihedral. I prefer to set the dihedral in the root ribs and forget about the tapered shim, but you can do it whichever way you prefer.
The product image is a Trainer 60 built by Scott Wallace.