The rocket body is a solid chunk of resin with finely cast and crisply molded details with no visible airholes. There are locater marks for the resin separation rockets (I think that's what those bulges are around the base of the upper stage adapter), the photoetched antennae (six are included in the kit, but only four are needed...), and the resin turbine exhaust. The main engine bell is hollow and has finely detailed cooling lines molded in place. The turbine exhaust part is solid: a hollow cast one would collapse upon removal from its pour plug. A steel pin is used for the nose spike. The instruction sheet includes a short program history, a single assembly drawing, and a four view painting and decal drawing showing all four quadrants of the Pioneer 4 launch vehicle.