Modular tsim, qhib nws tus kheej & kaw yam tsis muaj hluav taws xob hluav taws xob, tsuas yog xav tau kev teeb tsa yooj yim nrog lub hauv paus ntsiab lus ntawm dej buoyancy, ua kom nws yog koj daim thaiv dej nyab, nyab xeeb thiab txhim khu kev qha!
