US Patent 9969076 Connection device for hexagonal wrench

A connection device for a hexagonal wrench and includes a first part and a second part. The first part has an insertion section through which multiple hexagonal first recesses are defined, and an operation portion formed on one end thereof. The operation portion has multiple second hexagonal second recesses. The second part has a reception hole in which the insertion section is inserted and is positioned relative to the second part. The second part has an opening and the first recesses are exposed. The second part has another operation portion on one end thereof. The operation portion has multiple third hexagonal recesses. The first, second and third hexagonal recesses have different sizes and are Metric system and English system.