閉鎖 へいさ しきリブリーザーでしょう
heisa shiki riburiizādeshō

Noun
Desu Copula

Expresses probability in a polite manner ("probably…") of 閉鎖式リブリーザー

1. Closed-circuit rebreather; Probably a closed-circuit rebreather

Polite
Presumptive
Conjecture