Whether you cycle in the city or the countryside, a mask will keep the worst of the pollution out of your lungs. You will need to determine what type of environment you will be using the mask in. If you are commuting every day in heavy or slow moving traffic, you should use a City filter. Although chemical pollutants an be found in the countryside (crop sprays etc) particulates are more likely to be a problem so a Sportsta filter is the better option. The Techno includes both types of filter for the most complete protection.