Steel Tec is a metal construction toy, similar to Meccano. It used a combination of metal and plastic parts held together by metal screws.
First introduced in 1992, the Steel Tec system had a short and troubled lifespan, lasting only until 1997 when the Remco brand name was purchased by JAKKS Pacific, Inc. However, it has been reported that the Steel Tec name may yet again appear on a new line of construction sets under development by 4Kidz, Inc.
Unlike Meccano, the screws did not use a regular screwdriver, but an allen key. Sometimes the manufacturing tolerances were poor, and the screws were hard to use. Steel Tec uses the same thread as Meccano on it's nuts and bolts and wheel boss tappings - 5/32" Whitworth - unlike Gilbert Erector which used the American 8-32 thread.
The Steel Tec system was somewhat unique for several reasons. Most of the over 30 different sets that were produced during its five year run were designed to build just a single model. In addition, many sets featured an unusual combination of traditional metal parts (strips, plates, brackets, etc.) and molded and painted polystyrene components. Models built from these sets look like a strange hybrid of plastic scale model kit and metal construction toy. These featured models were often vehicles of some type (planes, trucks, spaceships, etc.) and tended to be small in size, since the largest standard metal part included in most sets was an 11-hole strip.
What's it worth? Take a look at this Steel Tec price guide: sold listings for a value indication.