mystery bottom bracket

[TrevorKershaw]

Hi Guys,

I found a bottom bracket in a box in the loft, it's a UN-54. What quality is this, as I can't remember. Is it LX?

 

[FluffyChicken]

It is Shimano modern top of the range square taper bottom bracket still used today but called un55 as the plastic cup switched to metal.
It is in a gap is above the old lx models but not quite what xt Xmas