Compatible Dyson DC03 tool set includes crevice, stair and brush tool

When would this part need replacing?
When the tools are split/broken
When the tools are missing

Will fit all DC03 models including:

DC03 Standard, DC03 Absolute, DC03 Absolute plus Zorb, DC03 clear, DC03 Zorb purple yellow, DC03 Independent.

Compatible Dyson DC03 tool kit TLS197