I’ve been asked about the ranks for
Warrant Officer is considered a very senior position in the army and those holding the rank of Warrant Officer are often on the staff and have a good record of service. Nowadays Warrant Officers can be sergeant majors, but Sergeant Major was originally a separate rank coming before Warrant Officer. Warrant Officers wear plain rank slides, and a wrist band on their right wrist or insignia on their sleeve. Although a Warrant Officer could potentially become a Second Lieutenant most warrant officers are paid up to double the wage of a Second Lieutenant.
A Warrant Officer class II is rarely addressed as Warrant Officer or Sir/Ma’am, but by whatever position they hold e.g. CSM WOII Jones would be addressed as “Sergeant Major”