HiKOKI 6686138 Oil Tank Cover for compatible Hitachi and HiKOKI pole saws and pole saw attachments. This replacement cover fits to the chain oil tank to help securely contain the lubricating oil and protect the tank opening from dirt and debris. Suitable for replacing a worn, cracked, damaged or missing original cover and manufactured to the correct specifications for precise fit. Part 6686138 replaces the previous part number 041-32304-20.