As the name indicates, the PT18 (PT standing for Petit Series) can accept a NUC motherboard. You get a 2.5" slot for fitting an SSD or a laptop-style hard drive, as well as any ports your donor NUC brings along. Holes for two USB ports and an audio output grace the front, while the back of the unit has holes for another pair of USB connectors, an Ethernet jack, and a set of display outputs.
The PT18 is compatible with 75-mm VESA mounts and is available in two versions, depending on the display output arrangement—the D2 variant has room for two Mini-DisplayPort connectors, while the H1D1 will fit NUC mobos with HDMI and Mini-DisplayPort outputs. The chassis measures 9.1" wide by 1.5" tall by 4.3" deep (or 230 x 38.8 x 110 mm) and comes with a vertical stand.