Obsolete parts belong to earlier generations of the Rascal Robot Construction Set and are no longer included in the set. Limited stock may still be available; if not, the part description will be marked "No stock". In some cases an "Alternate Source" link will take you to a major online supplier of the original part or equivalent.
In almost all most cases, obsolete parts have been replaced by improved versions as indicated in the obsolete part's description.
Improved parts are generally fully compatible with older parts, so you should expect no significant "misfits" of newer parts to your older Rascal set. In the descriptions of our current parts we will do our best to alert you to minor compatibility issues and how you can work through them most easily.