| Answer | Crossword Clue |
|---|---|
| BUTYL | Rubber used for inner tubes |
| BUTYL | Rubber used in inner tubes |
| BUTYL | Synthetic rubber used in inner tubes |
| SULPHUR | Element used for vulcanizing rubber. |
| NEOPRENE | Synthetic rubber used for wet suits |
| BUTENES | Hydrocarbons used in a substitute for rubber. |
