The SunTour X-1 was a perfectly respectable mid-market mountain bike derailleur of the late 1980s. It had the geometry of the SunTour XC-Pro, but the pulley cage and inner parallelogram plate were steel, etc. etc. - so far, so utterly unexceptional.
In its basic condition the SunTour X-1 sported a rather stealthy all-black finish. You could even call it tasteful in a Dieter Rams sort of way. But then a bad taste bomb exploded on the mountain bike scene - and fluorescent colours were de riguer. I have no proof that Gary Fisher was personally responsible for this style holocaust - but his dress sense is certainly circumstantial evidence.
How did component manufacturers react to this provocation? Shimano studiously ignored it, Campagnolo was unresponsive and in a coma and SunTour produced the X-1 Chroma - an X-1 with a bizarre clip-on plastic piece that came in a choice of lurid colours.
There were six 'Chroma' models in all, two different basic models, an earlier and a later model, each available with one of three clip-ons. The three clip-ons were rendered in fluorescent pink, fluorescent yellow or fluorescent lime green. The earlier basic model (CR00-GXB) had a tendency to flat surfaces and had 'X-1' written to the left of 'SunTour' on its outer parallelogram plate. The later basic model (CR01-GXB) had more fulsomely curved surfaces and 'SunTour' written to the left of 'X-1' on its outer parallelogram plate. Because of the different shape of, and different writing on, the outer parallelogram plates, the plastic clip-ons are also different for each model.
Handily, the Chroma clip-on clipped off as easily as it clipped on, and, if you didn’t remove it yourself (wearing sunglasses for safety reasons), it soon broke off of its own accord. Be thankful for small mercies.
This is a, very tidy, unused, example of the earlier CR00-GXB, with a pink clip-on.