Handles are parts to hold with hands for operating devices and machines. There are various types depending on the application, such as swing handles used for door handles and switchboards, latch handles used for communications equipment and specially-equipped vehicles, and T-handles suitable for doors that require higher sealing performance. The main materials are stainless steel, aluminum, zinc alloy, synthetic resin, etc. Swing handles are used in electrical enclosures as well as switchboards, and the direct-connected handle and clasp allow for smooth and forcible rotation. Latch handles feature easy opening and closing by simply pushing and pulling the door, and some are made of synthetic resin and lightweight. Some T-handles are equipped with dust-proof shutters and reversible keys, and it is necessary to select them to meet the purpose of use and the operating environment.