1.This bicycle bag expands the storage space for cyclists' bicycles by adding additional capacity to accommodate water bottles,beverages,tire tubes,tool kits,etc.Elastic ropes can help keep water bottles more secure and can accommodate bottles with a maximum diameter of 2.6 inches. 2.The bag is about 7 inches long,1.8 inches wide and 7.5 inches high.It is made of thickened nylon fabric,which is sturdy and durable.Large capacity,able to accommodate various small items that need to be carried with you during cycling,such as mobile phones,keys,etc. 3.The slim triangular bicycle bag won't interfere with your water bottle or rub your legs,and it has added waterproof fabric.A flat shape can reduce wind resistance and improve cycling performance.Perfect for long-term cycling or commuting.