United States Navy E-4/5/6 Boatswain's Mate Rating Badge
Worn by Boatswain's Mates (BM) with ranks from Petty Officer 3rd Class (E-4) to Petty Officer 1st Class (E-6). Boatswain's Mates are trained and supervise all activities relating to seamanship, including the use of marlinspike, and deck activities. They also are responsible for deck side watch. While in port three or more of the crew-memebers are on deck at all hours. They monitor all those coming and going and stand watch.
The badge is sold with all 3 chevrons below the rating for E-6, and can be tailored down to the other two chevrons.