T55-[TIme/Time]
This catagory is for recording work that doesn't fit into the R and T numbering systems. This includes work made mostly before 1994 ( which is numbered 1 + the last two digits of the year. 1984 = 184. Work after 2000 is numbered 2 plus the last two digits. 2006 = 206)

Also exhibitions of work from the T and R numbering systems can be found here.