You have trained yourself to use one particular kind of weapon with deadly efficiency.
Choose one type of simple or martial weapon with which you are proficient. You gain the following benefits when using the chosen weapon type:

• You can add double your proficiency bonus to your attack rolls with the chosen weapon type, instead of just your proficiency bonus.
• You can add your proficiency bonus to the damage you deal with the chosen weapon type.

You can take this feat up to two times, and you must choose a different weapon type each time you take it.