Our non-marking rubber stem casters work with most 1" diameter wire shelving posts and are available individually for replacements on existing setups or solutions without four posts. Sold individually, available in 4-packhere Ideal for transit over rough surfaces Stem acts as plug, fits into post's bottom Swivels 360 degrees for easy steering Non-marking, won't scuff floors For stability, not recommended for use with 8"d wire shelving