This record contains one Spacepen for the PDP-1. It is composed of a wooden table attached to a metal rack with wheels on its bottom. It contains X, Y, and Z axes and a loose plastic board that was once attached to the top of the axes (?). There is a pen that lodges into a brass "inkwell", which is connected to a power supply, and both of these are attached to a brass Sonic Pen 3-channel preamp (EDC-223), which is attached to the entire machine. With the machine are various cables, one of which ends in a terminating board that has cables for X, Y, Z, and "trig"; the board connects to the PDP-1. There is also a box with 9 switches attached to one of this cables.