The SEALFAST 4" Gray Fill Adapter Dust Cap is essential for protecting your fill adapters from dust and debris. Constructed from durable materials, this dust cap ensures a secure fit and long-lasting performance. It is designed to fit standard 4" fill adapters, providing a reliable seal that prevents contamination. This cap is ideal for use in tank truck applications, ensuring that your fluid transfer systems remain clean and operational. Its lightweight design makes it easy to handle, while its robust construction meets industry standards for safety and reliability.