A 25MM Gear Box Jack Extra Long refers to a specific type of jack that is designed to lift and support a gearbox or transmission of a vehicle. The extra long designation likely indicates that the jack has a longer reach or stroke than a standard gearbox jack, allowing it to lift the gearbox higher or support it from a greater distance. 25MM Gear Box Jack Extra Long can be useful for working on vehicles with high undercarriages or for providing more clearance when working on the gearbox itself.