This kit contains parts to build models of two of the first US lunar probes: Pioneer II and Pioneer IV. Resin base parts are also included to represent the floor of the launch platform and upper stage of each launch vehicle for displaying the models. The resin parts are molded with crisp details, a smooth surface finish and the only air holes I see are on the interior of the parts and won't be seen. There is some flash that will need careful removal from the more delicate parts. You will also have to open up the hole for the camera on the Pioneer II lower shell. Some of the tiniest parts are actually 3D printed and won't need much clean-up at all. There are some extra parts included of the most delicate parts, both resin and printed. Most of the parts have an ID number molded on the part itself or on the pour stub next to the part. A resin jig is included to set the proper angle for the steel pins that represent the antennas on Pioneer II. Very fine wire is included to represent despin weight lines on Pioneer IV. You will need to provide some household aluminum foil to represent Pioneer II's retro-rocket cover. The instructions consist of a printed page with last minute notes and corrections to the actual instructions on the CD-ROM PDF file. The PDF instructions consist of a parts list, general instructions on how to handle the parts and decals, and specific multiple assembly drawings with detailed text for each spacecraft along with painting and decaling instructions. The CD-ROM also contains photos of the real spacecraft and their launch vehicles, along with photos of museum displays and PDF files of NASA reports and other references.