This kit includes the ERS-220 head unit, leg units (x4), tail unit, and an OPEN-R version upgrade memory stick. The modules are exactly the same as the parts found on a retail 220 or 220A aibo, except from some markings.
The kit did not sell very well in Japan or abroad, so it is very rare to find a complete set with box. Sometimes preowned ERS-220s purchased from auction sites turn out to be 220 Transformation Kit parts put on a random aibo core.