1. Remove the old tire from both wheels and clean any remaining adhesive from the wheel surface. 2. Note: Do not use glue or other hard plastics. Suitable adhesives include neoprene, polyurethane, or rubber-based adhesives. 3. After applying adhesive, wait 5–8 minutes before attaching the wheel. Allow 24–48 hours for full curing before use. Positive and negative distinction: The tread pattern on the wheel cover is divided into two orientations: one for the ground side (referred to as positive) and one for the wheel side (referred to as negative). When installing the tire cover, ensure correct orientation—do not reverse the sides. Positive: From the outside, the lines are vertical. Negative: From the outside, the lines are horizontal. The positive side has lower resistance, while the negative side has higher resistance. Installing in reverse may reduce durability and shorten service life. Material: Plastic Color: Black Package Contents: 2 x Caster Wheels Note: Light and display settings may cause slight color variations between the image and the actual item. Measurement tolerance: ±1–3 cm.