A kit sold in 1989 as a build-to-order product. A combination of resin and brass, and a part of the model is movable.
As you can assume from the year it was sold, it was a replica model of the Endoskeleton from the first movie. The shape of the knees, and the groove that runs through the middle of the neck were copied as well.
The legs are made short, which closely resembles the Terminator in T1.
Since only a limited quantity was produced, and 20+ years has already passed since it had been sold, it is extremely difficult to get a hold of one, and the last time it was on ebay it was bid at a very high price.