Klipsch earphones use the smallest nozzle size available. Doing this allows the nozzle and housing to stay small for a more comfortable fit inside your ear and minimizes the room it takes up in your ear canal.
Other earphones with larger nozzles create pressure to the inside of your ear canal and cause discomfort.
Klipsch earphone drivers are the smallest in the industry and built in the housing unlike competitor’s drivers that are built into the nozzle. Doing this allows Klipsch to keep the housing and nozzle small. Larger housing means the nozzle and the tip will be larger and cause discomfort.