Crew book
An item that grants a lump of crew experience, the fastest way to bring a crew up to its next skill.
crew books, 개인 예약서(으)로도 알려져 있습니다.
Crew books come in national and universal forms and are earned from missions, campaigns and the battle pass. Using one adds experience directly to a crew, which is worth several hundred battles of training on a fresh vehicle.
They are the practical answer to the stock-and-untrained-crew stretch that makes a new Tier X miserable.