If you use my plugin: equip the item, and then remove it and put it back and you will see that in a line it changes between true / false
As S4000 told you
IBuff AquilaCuirass { get; } // 449064 - P4_ItemPassive_Unique_Ring_075 (data\player\powers\ILegendaryPowerInfo.cs)
Code:
plugin.RuleCalculator.Rules.Add(new BuffRule(449064) { IconIndex = 1, MinimumIconCount = 1, ShowTimeLeft = false, ShowStacks = false});
or
Code:
plugin.RuleCalculator.Rules.Add(new BuffRule(Hud.Sno.SnoPowers.AquilaCuirass.Sno) { IconIndex = 1, MinimumIconCount = 1, ShowTimeLeft = false, ShowStacks = false});