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Yes, I've ordered them from Chuck. It will fit any square taper BB. It's an older Truvativ model that they don't make any more. The 2 big rings are aluminun and the small is steel. It's a bargain if you want to stay with the square BB. It's probably equivalent to an older LX.The other thing you could probably do is to take the rings off and put them on your LX. Aren't the older LX 5 arm models?
Personally, everyone I know who has used the ISIS system has replaced the bottom bracket within a year. Shimano BB's tend to last several years, as do the cranks.