These caster wheel mounting plates are either bolted or welded onto the bottom of machinery, equipment or material handling carts. Quick change plates are offered in spring or quick change bolt versions. Caster mount shim plates are also referred to as weld plates and come with a pre-drilled bolt hole pattern that matches up with a variety of standard bolt hole patterns. Also available are bolt-on 4 position swivel locks and turntable caster mount plates.