The concrete vibrator is used to consolidate cement and remove all the trapped air bubbles to give you the toughest cement possible. It is transmitted by flexible shaft, speed increased through planet structure, then gain high frequent vibration.Matched with concrete vibrator: Vibrator diameter: 28mm,32mm,38mm,45mm,50mm,60mm,70mm Coupling type: Malaysian type, Japanese type and round typeThe length of flexible hose is according to the customer's requirement.usually it's 6M.