This Stage Plus heavy-duty braked swivel castor (supplier part M-STA-W9002-V1) has a 100 mm blue wheel and is used on flight cases, road trunks, equipment racks, staging and dollies built by Stage Plus and by case makers and technicians doing their own builds or repairs. A swivel castor rotates freely through 360 degrees so a loaded case can be steered easily, and the integrated brake locks the wheel so the case stays put on a stage, in a truck or on a sloping floor. A 100 mm wheel is the common size for road cases and racks, rolling easily over cables, thresholds and uneven floors while keeping the case low. Castors are normally used in sets of four, often two braked and two unbraked, and are bolted to the case base or a castor dish. The listing is for a single castor; mounting hardware is not specified. Stage Plus is the South African flight case and staging brand of AV Distribution, which manufactures custom cases, Pro Line cases and trunks locally, so this is a useful spare for replacing a damaged wheel on an existing case.