Blue Block Lens, peb kuj hu nws Blue Cut Lens los yog UV420 Lens.Thiab nws muaj ob yam sib txawv xiav thaiv lens, ib qho yog cov khoom siv xiav thaiv lens, hom no yog thaiv lub teeb xiav los ntawm cov khoom siv; lwm qhov yog ntxiv xiav thaiv txheej los thaiv lub teeb xiav.Feem ntau cov neeg siv khoom xaiv cov khoom siv xiav thaiv lub lens, vim nws pheej yig dua thiab yooj yim los xyuas nws cov block muaj nuj nqi, tsuas yog xav tau lub teeb xiav cwj mem yog txaus.