OVERALL GLIDE HEIGHT 35mm overall glide height when installed, fits for most small chair casters This stool office chair bell glides can convert office chair with casters into a stationary chair without losing the chair height. ✔DIMENSION OF INSERT STEM The standard 7/16 x 7/8 inch (11 x 22 mm) grip ring mounting stem to attach to most standard chair or stool bases, Suitable size can meet your needs Please refer to the size carefully before purchase to confirm the prop