Right now the girdle works by limiting the charges to min(5, armorPieces), but that rewards players who wear more armor.
The item should be limited by max(0, 10-armorPieces), that is, the icons should appear on the right of the armor meter, and should only occupy "empty" armor meter slots. This way players will be rewarded by wearing less armor.
The networking/capability should also be reworked, moving away from the SimpleCapability implementation as it will be removed in the future