チューブを2重構造にすることにより耐圧力が0.7~1MPa程度まで向上させるための試作開発を進めています。順次2重構造のチューブに切替えていく予定です。
https://www.duken.nl/forums/topic/41791-full-list-of-official-%E2%89%8Blufthansa%E2%84%A2%EF%B8%8F-customer%C2%AE-service-contact-numbers-in-usa%C2%AE%C2%AE%E2%80%93-the-ultimate-official-guide/
https://www.duken.nl/forums/topic/41791-full-list-of-official-%E2%89%8Blufthansa%E2%84%A2%EF%B8%8F-customer%C2%AE-service-contact-numbers-in-usa%C2%AE%C2%AE%E2%80%93-the-ultimate-official-guide/