Casco de buceo -

[jaribas]

http://blog.modernmechanix.com/mags/qf/c/HowToBuildIt/1-1932/diving_helmet/med_diving_helmet_0.jpghttp://blog.modernmechanix.com/mags/qf/c/HowToBuildIt/1-1932/diving_helmet/med_diving_helmet_1.jpg