1. You just need paste the stainless steel universal wheel on the bottom of , that can move these heavy objects such as Toy Bins,Bottom Storage Box, Trash Can, Shoex Box etc. 2. The upgraded version is made of thicker material, and there are more stainless steel sliding beads into the bottom, which is smoother than the version when moving. 3. Tear off the film of sticker, firmly press onto the clean and surface of box.It is better to install this universal wheel to the four corners to achieve balance and better capacity. wait for 24 hours to move sticky wheels , so that stickers will be stronge 4. Suitable for small spaces, such as storage boxes under the bed, shoe boxes. It can also allow children to move their toy boxes.[Note]Ad indicates a max weight capacity of 17Lbs (8kg) 5. Suitable for dormitories, apartments, home bedrooms, kitchens, living rooms, etc. These mini caster wheels are suitable for different types of storage boxes. It can be applied to bookshelves, shoes box, toy bins, trash bin, small container for & easier moving. Product Name: Ball Type Adhesive Pulley Colour:White Material:ABS+stainless steel Size:4.5 x 2.8cm Package Contents: 16 x Self Adhesive Wheels Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.