Manufactured by a company now out of business, the Chien Yen Iron Works Co. Ltd. of 107, Chien Street, Chu Li Shih Lin District, Taipei, in Taiwan, Chien Yeh lathes appeare to have been of good quality and with a decent specification. Not as well known as that other common Taiwanese lathe the "generic", as manufactured from the 1970s, the smaller Chien Yeh models of the same era were of a similar size -  but complimented by a range of larger machines. Unfortunately, little written evidence survives as to the extent of the company's range, but earlier machines appear to have been listed in two groups: as engine types, with full screwcutting gearboxes and power sliding and surfacing feeds, and as simpler models with screwcutting by changewheels and just power sliding using the screwcutting feed.
Engine types (centre lathes in UK parlance) made during the early 1970s, consisted of the smaller, geared-head 7-inch centre height CY-600AS and CY-500AS, this pair differing only in their capacity between centres - respectively 42 and 30 inches. While they were fitted with their own design of single-tumbler, twin-lever screwcutting and feeds' gearbox, they were fitted with the same design of carriage as the heavier FGK types.
Surprisingly, instead of geared headstocks, the larger lathes had belt-drive headstocks, and were listed as the 9.5-inch centre height CY-8FGK, CY-7FKG, CY-6FKG  with, again, all having an identical mechanical specification but taking between centres, respectively, 56, 44, and 32 inches. A single smaller model in this range, CY-5FKG was also listed, this being of lighter proportions with a 7-inch centre height, 30 inches between centres, fitted with a more limited threading range and a less powerful motor. All the FKG lathes had a twin-tumbler screwcutting and feeds gearbox clearly modelled on that fitted to the "Generic" models - though the rest of the lathe was entirely different.
By the 1980s, larger, more powerful models were offered, these all having geared headstocks and a massive, heavy-looking build.
Full specifications details, though little else, is listed in the catalogue below from the early 1970s.