 Sardegna was armed with a main battery of four 13 @.@ 5 in ( 343 mm ) 30 @-@ caliber guns , mounted in two twin @-@ gun turrets , one on either end of the ship . She carried a secondary battery of eight 6 in ( 152 mm ) 40 @-@ cal. guns placed singly in shielded mounts atop the upper deck , with four on each broadside . Close @-@ range defense against torpedo boats was provided by a battery of sixteen 4 @.@ 7 in ( 119 mm ) guns in casemates in the upper deck , eight on each broadside . These were supported by twenty 57 mm ( 2 @.@ 2 in ) 43 @-@ cal. guns and ten 37 mm ( 1 @.@ 5 in ) guns . As was customary for capital ships of the period , she carried five 17 @.@ 7 in ( 450 mm ) torpedo tubes in above @-@ water launchers . The ship was lightly armored for her size . She was protected by belt armor that was 4 in ( 102 mm ) thick , an armored deck that was 3 in ( 76 mm ) thick , and her conning tower was armored with 11 @.@ 8 in ( 300 mm ) of steel plate . The turrets had 4 in thick faces and the supporting barbettes had 13 @.@ 75 in ( 349 mm ) thick steel . 
