A Fiber Optic Splice Closure, also known as a fiber optic joint closure, is a device used to protect fiber optic splices while providing fiber connections. With an IP68 rating, it is suitable for various harsh outdoor environments, including wall or pole mount, aerial lines, underground ducts, and direct burial applications. According to their structural design, closures are mainly divided into three types: In-line Type, Butt Type, and Dome Type.