Blind inserts are inserts that are closed at one side. They are used in applications where it is important to keep a screw isolated from certain assemblies, such as electronic circuitry. They assure that dust, chips, and other foreign objects will not contaminate an assembly.
The Blind Insert is primarily used in environments where contamination is not allowed. When the sheetmetal is thin, and there is no option to make a blind hole, a Blind Insert can grant you the same benifits.