100+cc Pro model
Was discontinued quite a few years ago.
690 with less displacement had basically equal power.
690 was also discontined, and eventually replaced by the 694.
Saw was pretty much of quality conventional nature, based on the 680-690 chassis.
Cylinders (NikaSil coated) were mostly made by Solo using the variable transfer port window that is become more common today in consumer-semi pro saws.
However, it was one of the first to incorporate both a four transfer port, and the varaible window port.
Engine rpm was about 12K