Floor Protection: Made of Steel Material, Silent Rubber Roller, Will Not Damage the Floor. Size: Stalker 1.5 Inch/ 38Mm; 2 Inch/50Mm; Insert Stalk Size-8*38Mm. Easy to Install: Just Pull down the Currenters and Push or Screw into Our Chair to Change the Wheel. Smooth and Precise Scrolling: Super Smooth Scrolling, No Noise When Scrolling, No Interruption Duwork. Easy Installation: Designed for Quick and Simple Installation, Theseor Wheels Offer Long-Term Durability, Ensuthey Stay Securely Attached and Perform Smoothly over Time., Manufacturer: CHAOUYYZ