This garment is rumored to have begun as a simple, loose-fitting tunic, but the true origins are clouded with conjecture, and often seems the fabric of a tall tale crafted by a retired Outer Rim smuggler. Because of the engineer vest's long-standing existence, and the few design changes made to it over the last hundred years or so, separating the legend from the surrounding facts is often difficult.
The garment is sleeveless, according to popular belief, because the original designer watched a colleague's loose sleeve catch on a rapidly revolving piece of a generator and pull him through the workings up to the shoulder. It is relatively form-fitting for a similar reason, since according to the same legends, the originator saw his best friend's loose-fitting coat pull him into an early plasma turbine engine.
The vest in its current style is made of three melded layers of fabric, all of which are crafted for specific properties. The inner-most layer is designed to act as an insulator, both to help the wearer maintain homeostatic temperature control on their torso, and to help protect them from electrical shock. The middle is a thick layer of highly elastic polymer, which ensures that the garment remains more or less molded to the torso to prevent accidental entanglement in moving parts. The outer layer is made of a moisture and heat resistant synthetic blend fabric.
Additionally, the engineer vest contains five main pockets, which are placed with kinesiologic and ergonomic function in mind. There are two upper and two lower torso pockets, and a large pocket across the lower back of the vest. These are designed by decreasing the width of the middle layer in these areas to the minimum, and creating an opening across the outer layer which can then be fastened through the use of the same conditionally adhesive substance which is affixed to the front, allowing it to be fastened and unfastened for access. The placement of these pockets, and their design, permits the wearer to store up to four kilos of tools, documents, items, and other small and sundry things without any noticeable difference in the weight of the vest on the body.
Smugglers and other less-than-honest individuals sometimes use this vest, in their trade. The back pocket has sufficient capacity to hold a small hand-held blaster, and a creative tailor can easily place additional small pockets about the inside of the vest which can be hidden in its seams. These can carry no appreciable weight above the above-mentioned limitations, however, are the perfect size for hiding data cards, raw material samples, or pilfered trinkets.