Professional Installation: It is recommended that the camera repair part be installed and removed by a professional repairman. Long Lifespan: This lens zoom grip ring is made of plastic material, light weight, hard to crack, high temperature resistant, flexible, highly impact and scratch resistant. Professional Tools: The shape and size of our lens zoom grip rubber rings are designed accurately and can work normally after correct installation. Perfect Substitute: It is a perfect substitute for the original parts lens whose rubber cover is damaged, broken and unusable. Compatible: Camera lens zoom rubber is suitable for Sigma 18‑200 Lens. Please confirm the model before use.