In the German military, the appointment of Hauptfeldwebel was the German equivalent of a Commonwealth Company Sergeant Major or American Company First Sergeant. There was one such non-commissioned officer (NCO) in every infantry company, artillery battery, cavalry squadron, etc. He was the senior NCO of his subunit, but his duties were largely administrative and he was not expected to accompany his unit into an assault or a firefight.
The Hauptfeldwebel had many nicknames, including Spieß ("Spear") and Mutter der Kompanie ("company mother"). He wore two rings of NCO braid around the cuff of his sleeves (nicknamed "piston rings") and carried a Meldetasche (reporting pouch) tucked into the tunic front, in which he carried blank report forms, rosters and other papers related to his duties. The German Army had no equivalent of the Commonwealth Regimental Sergeant Major.
The appointment could be held by a senior non-commissioned officer (Unteroffizier mit Portepee). If the billet was filled out of necessity by an Unteroffizier ohne Portepee, he was termed a Hauptfeldwebeldiensttuer, or "one serving as Hauptfeldwebel."
Hauptfeldwebel (HptFw or HF) is the third highest Non-commissioned officer (NCO) rank in German Heer and Luftwaffe.
It is grouped as OR7 in NATO, equivalent to a US Army Sergeant 1st Class, US Marine Gunnery Sergeant, or US Air Force Master Sergeant, and to Warrant Officer Class 2 in the British Army and Royal Navy.
In army/ air force context NCOs of this rank were formally addressed as Herr Hauptfeldwebel also informally / short Hauptfeld.
The sequence of ranks (top-down approach) in that particular group (Senior NCOs with portepee) is as follows:
The abbreviation "OR" stands for "Other Ranks / fr: sous-officiers et militaires du rang / ru:другие ранги, кроме офицероф"!
The Hauptfeldwebel was introduced by the German Wehrmacht in 1938 not as a military rank but as the assignment to “company sergeant (de: Kompaniefeldwebel or Spiess). Most experienced Protégée-NCO with the rank Stabsfeldwebel or Oberfeldwebel (more seldom Feldwebel) have been assigned to that distinguished position.