Drivers have to manually double-clutch and match the motor speed into the gear velocity, which may be difficult. This structure is largely out of date today but stays a fascinating piece of automotive record.  Contohnya ketika menuruni bukit Cameron Highland atau Lebuh Raya Timur Barat (bukit Gerik) dengan equipment D, https://gearboxauto10853.uzblog.net/an-unbiased-view-of-gearbox-kereta-auto-46407774