noun
regular production; current model
Used in manufacturing and business contexts to refer to the standard, mass-produced version of a product, as opposed to prototypes or limited editions.
この部品は号口品として安定供給されています。
This part is supplied stably as a regular production item.
試作品から号口への移行には慎重な検討が必要だ。
Careful consideration is needed when moving from a prototype to regular production.
Compound of 号 (number, designation) and 口 (opening, item). The exact derivation is uncertain, but it likely originated as industry jargon for a numbered production item or standard specification.