This spacer is used in oldschool Roces skates like the Roces Fco and Roces Street models.
The modern Roces 1992 skate also has these spacers in them.
They are a perfect upgrade for the oldschool skates that come with the "aero light frame" and the "street frame". These oldschool frames often had nylon frame spacers in the cheaper models. If you use these spacers instead then the skate will be faster and more responsive. A cheap and easy upgrade to make your oldschool skate better.
The spacers are sold per piece