Ball casters are a stylish way to put wheels on occasional furniture pieces such as ottomans, desks, tables, etc. Unlike your typical swivel caster, they only require minimal floor clearance and have an appealing rather than industrial appearance and the antique brass finish is compatible with most furniture pieces. Tech Team's #917 set of 4 is supplied with 4 – 4 prong insert sleeve bushings so that they can be used to replace existing casters or used for a new installation.