Proline 35618 is a 3/8" inlet x 3/8" outlet straight coupling mechanical fitting, made of brass and zinc. The fitting is designed to be used in liquids and gasses applications making it suitable for plumbing, refrigeration, and compressed air systems. The 35618 also has high temperature capabilities, making them suitable for use in hot water or steam systems. This fitting is lead-free and meets EPA and NSF/ANSI standards.