Professional writing marker - High quality with long lasting durability and smooth consistent ink writing. 

One side is      - 1.0 mm - Fine Line Marker Tip

Second side is - 0.5 mm - Fine Liner Tip

Best use for professionals, hassle free switch to marker to fine line, now you don't have buy and keep 2 writing tools separate as you are getting them in one. Helps in better organizing your Desk with less and only useful tools around you.