diff --git a/ObservatoryFramework/Files/Journal/Powerplay/PowerplayVoucher.cs b/ObservatoryFramework/Files/Journal/Powerplay/PowerplayVoucher.cs
index 76fbeeb..d7a24d5 100644
--- a/ObservatoryFramework/Files/Journal/Powerplay/PowerplayVoucher.cs
+++ b/ObservatoryFramework/Files/Journal/Powerplay/PowerplayVoucher.cs
@@ -2,7 +2,6 @@
 {
     public class PowerplayVoucher : PowerplayJoin
     {
-        //TODO: Find out what this is actually supposed to be. Documented as "Systems:[name,name]"
-        public string Systems { get; init; }
+        public ImmutableList<string> Systems { get; init; }
     }
 }