[PERFECT DESIGN STYLE]: The office chair wheels are in single-wheel mode, not double-row wheel mode, which makes everyone more beautiful and practical. Our heavy duty chair casters are made of transparent polyurethane material with solid steel fabric precision ball bearings, which makes the office chair more stable and firm, let everyone rest assured (our stem size is 7/16 x 7/8) [SUITABLE FOR MOST OFFICE CARTS]: The outer layer of the casters is made of PU material covered with soft polyurethane. This soft shell not only prevents damage to your floor, but also rolls freely on the carpet. Our office chair wheel replacement will never scratch, stain or damage your floors. Of course, if the chair cushion needs to be used, the casters can also work well. Enjoy worry-free and safe gliding on wood, hardwood, laminate, vinyl, tile and carpet floors all day long. [EASY TO INSTALL AND STURDY]: Installing the casters is very simple - no tools are required. [SMOOTH AND QUIET GLIDE]: The casters