Combiner / Bicycle accessory parts

More and more people choose riding bicycles.Existing bike mainly city ,mountain and racing bicycles.Bike is commuting tool in urban traffic,don’t need high speed but requires comfort.Sometimes people desire a sense of speed, they want to get irritation.Consumers have to buy two different bikes to reach two functions,not only waste space and money,reduce efficiency but waste resources and do harm to environmental protection.Combiner add an additional function on handle,making it able to change the length,which can achieve the purpose of changing the riding position,quick,easy,while reducing waste,more economical and environmentally friendly.